Ask Our Garden Experts: Questions and Answers from 2019

If you have a gardening question, you are welcome to

Questions and Answers from 2019

Answers are provided by Donna Coffin, Extension Professor, Penobscot & Piscataquis Counties; Caragh Fitzgerald, Associate Extension Professor, Agriculture, UMaine Extension Kennebec County; Kate Garland, Horticultural Professional, UMaine Extension Penobscot County; Pamela Hargest, Horticulture Professional, UMaine Extension Cumberland County; Kathy Hopkins, Extension Educator, UMaine Extension Somerset County; Tori Jackson, Extension Educator: Agriculture and Natural Resources, UMaine Extension Androscoggin and Sagadahoc Counties; Kathleen McNerney, Home Horticultural Coordinator, UMaine Extension Cumberland County; Marjorie Peronto, Extension Educator, UMaine Extension Hancock and Washington Counties; Elizabeth Stanley, Horticulture Community Education Assistant, UMaine Extension Knox, Lincoln, and Waldo Counties; and Frank Wertheim, Extension Educator, Agriculture/Horticulture, UMaine Extension York County.

Q: A neighbor just brought me a Magnolia branch that broke off his tree. We live in Cushing, Maine. Can you advise me on what I need to do with this clipping/branch in order to plant it in the Spring?

A: It sounds like the branch which broke off would be considered a hardwood cutting (that is a dormant, mature stem). The best type of cutting for rooting a magnolia would be considered a semi-hardwood cutting (partially mature wood of the current season’s growth, just after a flush of growth).

Having said that you can certainly give it a try.

Where it has broken off cut it again with a pruning clipper to get a nice straight clean cut at the bottom. You should dip the end in a rooting hormone that can be purchased at a local garden center. Then place the cutting in a plastic bag with some moist (not soaking) sphagnum moss or wood chips and place it in your refrigerator for the winter. In spring bury the cutting in your garden such that only the top few inches of the growing point are exposed.

A second method would be to treat the cutting with a rooting hormone as suggested above and place it in a flowerpot with vermiculite as your rooting medium. Well-drained potting soil can also be tried if that is what you have on hand. Moisten the medium well and place the pot and cutting in a plastic bag. Keep it in bright light but try to avoid direct sun and make sure it stays moist until rooting has occurred.

A more detailed description can be found in this fact sheet from North Carolina State University on Plant Propagation by Stem Cuttings.

Q: Help! I have a mouse infestation in my high tunnel, which is an 8′ x 8′, cattle panel construction with a raised bed on each side. House mice have completely destroyed all the plants in one bed, and I see evidence of tunneling in the other bed. There is no way for me to build a skirt to exclude them from tunneling in this season.


  1. I hesitate to even eat the remaining plants, given the likelihood that mice have been crawling among them. Can I safely clean the plants, or should I toss this year’s winter greens to the chickens?
  2. Snap traps are not doing the job. I’ve searched extensively for information about poisons that can be safely used in the garden. I don’t see the anticoagulant poisons on the market anymore, only the neurotoxin ones. My concern: What is the breakdown period for these NT pesticides? Mouse or rat eats the bait, crawls in the hole to die. Corpse rots. How does that affect soil microbes, soil chemistry, and plants that uptake the end product of composted, poisoned mouse?
  3. I would love to see an article about this topic or be directed to written material that deals with the issue of rodenticides in the garden. (Not a could you, should you article, but actual facts about how these chemicals break down in the garden)

Thanks so much for all the info I can glean from your site!

A: Below is a response from the State Toxicologist with the Maine Board of Pesticides Control, Pam Bryer. With respect to your first question, I would avoid eating the remaining greens if you are certain they’ve been contaminated by mouse droppings.

As prep for a talk I did recently I went to my local big box store to see what types of rodenticides they were selling. You are right in that many of them are the neurotoxic bromethalin but there are also two others you might be interested in cholecalciferol and zinc phosphide. And, by the way, if you were to hire a commercial pesticide applicator they would be able to use a different set of pesticides as well (namely the anti-coagulants).

Bromethalin: persistent in soil, doesn’t volatilize, doesn’t wash out, highly likely to transfer up the food chain, not carcinogenic, moderately toxic to soil invertebrates, and highly toxic to mammals. If it were used in the scenario you mentioned it would persist in the soil for some time but it would be difficult for it to be translocated into the plant tissues. Essentially, because it binds tightly to organic matter and is a large molecule it would be difficult for the plant to take it up in significant quantities. Also, you are looking at a volume dilution effect. Rodents are more susceptible to these poisons than humans so a lower dose is used to kill them than would kill us — plus we are much larger and would need many more times the dose than it would take to kill some mice. That said, because of its persistent nature and bioaccumulation potential and toxicity it would be best to avoid that if you can in a garden space.

Cholecalciferol: not persistent in soil, doesn’t volatilize, doesn’t wash out, low likelihood of transferring up the food chain, not carcinogenic, moderately toxic to soil invertebrates and mammals, and low toxicity to birds and fish. Cholecalciferol is another name for vitamin D. Rodents are more susceptible to vitamin D overload than humans, and other mammals, are which makes this a less risky pesticide to use around humans. Because it breaks down in the soil quickly, 97% will be degraded within ~25 days, this becomes a better choice for a garden area. Again, like above, the dilution of the chemical within the soil, and then the plant, and then folks who eat that plant, the actual amount of active ingredient would be unlikely to cause effects. This rodenticide acts by disrupting calcium balance in the body; excess calcium is released from the bones and leads to multiorgan dysfunction.

Zinc phosphide: not persistent in soil, doesn’t volatilize, doesn’t wash out, not carcinogenic, low toxicity to soil invertebrates, moderate toxicity to fish, high toxicity to mammals. This compound to changed by the low pH of the rodent stomach into phosphine gas. Phosphine is very volatile and moves quickly into the lungs where it acts to prevent normal respiration and death ensues. The amount of phosphine that is generated is unlikely to harm humans and it ends up dissipating quickly. Phosphine (or a precursor) is used in agriculture as a soil fumigant and agricultural storage fumigant.

I’m sorry I don’t know of any good summary article for you because your question is a good one that I’ve only scratched the surface of. I’ve provided the links that I used from a database that is a good reference because it offers some qualifying words and not just straight numbers.

In all these cases, care must be taken to avoid access to the rodenticide by pets. The primary cause of pet death with rodenticides is from the pets eating the baits, and this makes sense, those baits are made to smell good. There is some concern with secondary poisoning (pets eating a mouse that died from eating the poison) but these particular over-the-counter pesticides are allowed to be over-the-counter specifically because the risk of secondary poisoning is very low, theoretically possible but unlikely.

Another precaution is that in order for a pesticide to be used in Maine it must be registered with the state by the Board of Pesticides Control. We simply can’t monitor all the Internet for pesticides available for sale and rely on vendors knowing the rules and citizens learning about the rules. If you find a pesticide on the web and are interested in purchasing it, you can check it against our database or you can call our office at 207.287.2731. Pesticide registration changes each year so it is best to check each time you go to buy something off the Internet.

If you have other questions please feel free to contact me:

Pam Bryer

Also, there might be some alternative physical traps available. Last winter at my house we used a little black box that electrocuted the mice as they reached for some peanut butter bait. We got them at the local hardware store. We caught 13 mice in 48 hours! A little light flashes when you’ve caught one so you can empty the trap, and the body just dumps out so no mess. I offer that as a personal story and am in no way trying to imply that the State of Maine wants you to buy that or not buy that or buy a conventional rodenticide or not buy a conventional rodenticide! I have a little background in applied animal welfare so quick death devices are always on my radar.

Kathy Murray, the IPM Coordinator, Department of Agriculture, Conservation, and Forestry just ran a “Rodent Academy” which was a 2-day seminar for applicators. She might have some fresh ideas floating around in her brain. Here is her contact:

Kathy Murray

28 State House Station
Augusta, ME 04333
phone: 207.287.3891
fax: 207.287.7548

Best of luck!

Pamela J. Bryer, Ph.D.
Board of Pesticides Control
Department of Agriculture, Conservation, & Forestry
90 Blossom Lane, AMHI Campus, 3rd Floor, Deering Bldg., Augusta, ME 04333
Mailing address: 28 State House Station, Augusta, ME 04333-0028

Q: I was walking on my property, about 6 acres near Sebago Lake in Naples. We are situated on top of the hill. A few years ago, I had a lot of healthy young pine saplings about my height or slightly shorter. During my walk, however, I have noticed that these groves are all completely dead. All the needles are orange, save a few trees that have green at the top, and I can pull them out of the ground with zero effort. Their trunks range from 2-inch diameter trunk to smaller. I can’t see any visible signs of fungus or anything else, but they do look somewhat withered and blackened and slightly distorted.

A: UMaine Extension’s Plant Pathologist, Dr. Alicyn Smart, says the following in response to your inquiry:

“Orange always makes me think a rust, but knowing what kind of pine would be helpful. Orange could also just be the red-brown that needles become when they are dead, so that is up for interpretation. If it’s dead, then pulling the plant out of the ground would be easy. But if they have a root disease, they would also be easy to pull out. A rule of thumb in many labs, even when you have a sample in front of you is to not diagnose until you have a photo of the entire tree since so many things could occur with a tree declining. I would ask for a photo, what kind of pine and what the roots looked like when they pulled it out. These will help sort out what the problem might be.”

So, if you have any photos of the declining pines, please send them to your local UMaine Extension county office and we’ll work with Alicyn to try to diagnose your problem.

Q: I bought zinnia plants last summer, just ordinary zinnias. Today, while pulling dead frozen plants, two plants had clusters of potato-looking rhizomes at the bottom of the roots about the size of golf balls. What are they?

A: Since zinnias don’t produce bulbs or rhizomes, I suspect they are either part of another plant or the plants you got were mislabeled (perhaps dahlias?). If you believe they are dahlias or some other tender bulb, this site from the University of Minnesota Extension, Time to Store Your Tender Bulbs, has good instructions for digging and storing them over winter.

Q: How do I prepare highbush blueberries for winter? I have two in a small plot, same species, producing well but only below the snow line. They are now three years old. Should I prune back to the expected snow line for this winter, or wrap with burlap to protect from winter winds, or just mulch and leave them alone? I am in the central Maine area.

A: A 4- to 6-inch layer of mulch will help protect the roots from frost damage and help maintain adequate moisture in the spring and summer. I would not recommend pruning back to the snow line because fruit is produced on new canes and you would be removing most of the new growth. Since your bushes are three years old you should start yearly pruning, when plants are fully dormant (late winter to early spring) following the directions in Bulletin 2253, Growing Highbush Blueberries. The video below, Blueberry Bush Pruning, also demonstrates how to prune. If the variety is sufficiently hearty it shouldn’t need winter protection but it sounds like your bushes may need some extra protection, so burlap could help.

Q: My garden is 19′ x 26′. I’ve traditionally covered it with a tarp in the fall, to keep weeds down in the spring and warm the soil (and because I think it looks nicer through the winter and protects the soil from being blown away as we’re on a hill). I don’t have perennials in the bed and just pull up a corner where I’ve planted the garlic in the spring. My husband questions if using a waterproof tarp is a good or bad idea. It’s too late to consider a cover crop this year.

A: Tarping (with plastic), along with cover crop and mulching are all great ways to protect your soil from erosion over the winter. A lot of research is currently being done on the benefits of tarping for organic and no-till farms. If you are considering a change for next year, cover crop provides living roots in the soil, which benefit soil organisms and provide organic matter to be incorporated the following spring. However, depending on equipment, dealing with a cover crop in the spring can be a challenge. Bottom line, if using a tarp is working for you, and isn’t creating any problems, there’s no need to stop!

garlic; photo by Edwin RemsbergQ: Is it too late to plant garlic this year? If not, how deep should I plant it?

A: If you are in central and southern Maine, it is not too late to plant garlic. In fact, late October is the perfect time. The goal in the timing of planting is to allow the clove to establish a root system but not to plant so early as to have the top emerge above the soil line where it is prone to winter injury. Try to get it in the ground this weekend!

Garlic cloves should be planted with their pointed ends up so the clove point is 2 to 4 inches below the soil surface. Space cloves 4 to 6 inches apart within rows, and space rows from 6 to 12 inches apart. Here is a University of Maine Cooperative Extension bulletin on Growing Garlic in Maine, which includes several short videos on planting, harvesting and storing garlic. Follow the instructions outlined in the bulletin, and you should have a beautiful crop!

Q: We have recently purchased a house in Southwest Harbor and would like to plant a hedge along one side of the yard. We’d like the hedge to be about 5′ high and provide privacy. We also need something that’s deer resistant. Arborvitae has been suggested, but I’m looking for other alternatives. Can you give me any other suggestions? I’d love to have a laurel hedge. Will that work here? Alternatively, what about yew?

A: Your choice of what you plant for a hedge should first be determined by hardiness and site conditions. In Southwest Harbor, you are in USDA Hardiness Zone 5A, so be sure to purchase something that is hardy to that zone, or to be safe, hardy to zone 4.

Have a look at the following publication to find native shrubs that would suit your height preferences. Preferred growing conditions (sun, shade, moist, dry, etc.) for each shrub are listed. You will also need to decide if a deciduous shrub is okay for screening, as leaves will not be present in the winter. You may prefer an evergreen, but your choices will be much narrower. See Gardening to Conserve Maine’s Native Landscape: Plants to Use and Plants to Avoid.

In terms of deer resistance, here is a good website from Rutgers University that ranks plants by level of deer resistance, Landscape Plants Rated by Deer Resistance.

Some recommendations I have from personal experience are:

Deciduous shrubs:

  • Diervilla lonicera
  • Northern Bush Honeysuckle (not a true honeysuckle)
  • Ilex verticillata, Winterberry (need separate male and female plants to get fruit, which persists through winter. Cultivars vary in height)
  • Morella caroliniensis (formerly Myrica pensylvanica)
  • Northern Bayberry (can grow taller than 6′ but can be managed with pruning)
  • Pieris japonica
  • Andromeda (height managed with proper pruning)
  • Sambucus canadensis (height managed with pruning)
  • Swila (formerly Cornus) sericea
  • Red-Osier Dogwood

Evergreen shrubs:

  • Taxus canadensis (Canadian Yew)

Q: I recently moved into a new house, and had to start a new yard from seed, in the middle of August. As you might expect, we got lots of crabgrass. I pulled much of it and the grass has filled in, but I still need to seed again next spring to fill in bare spots. I also would like to apply a pre-emergent crabgrass herbicide to keep out the crabgrass next year. Do I need to wait until the grass seed sprouts before applying pre-emergent? How long after planting grass seed should I wait to apply the pre-emergent? And how late in the spring can I apply the pre-emergent and still have it effectively prevent crabgrass?

A: This will be tricky. Preemergence herbicides work by inhibiting the growth of young seedlings. Maine’s State Horticulturist Gary Fish states, “The only pre-emergent you could use is Tupersan when seeding. Unfortunately, you missed the better window of opportunity after crabgrass senescence (dieback). You might even want to dormant seed it now. There is no way to sow early and use regular crabgrass control and get any control.” If you’d like to discuss his recommendations further, he can be reached at . or call 207.287.7545.
These University bulletins may be helpful for future reference:

Q: I am new to Maine, and have very limited knowledge about gardens. However, I happen to have bought a house with an extensive one. I hope to find a Master Gardener in the area of Harpswell, who can not only give me some guidance, but can also work in the garden. I would pay an hourly wage. Would you give me recommendations or tell me where I could advertise?

A: I recommend you contact the UMaine Extension Cumberland County office directly and speak with the person who coordinates the Master Gardener Volunteer Program. She may be able to get the word out to local Master Gardener Volunteers about your employment opportunity.

Q: We are moving to Cumberland, Maine this December. We would like to plant two apple trees in the Spring, Macoun and Blue Pearmain, both grafted to keep them dwarfed. Do you know how I could find these, and if they would do well in the Cumberland area?

A: Both of the apple varieties you’ve selected are hardy to Zone 4, so you should not have any trouble with winter hardiness in the Cumberland area. Some popular sources of apple trees include:

I suggest you have a look at our website, Growing Fruit Trees in Maine, for helpful suggestions on planting, fertilizing, pruning, and general care.

Q: I have been gardening in the same 30×60 plot for 40 years, growing mostly tomatoes, sunflowers, and squash. Although I try to carefully rotate the crops within that space, there are only so many possible configurations. I have generally had some fungal disease, which I have treated by cutting off diseased material and either burning it or putting it into the trash, and also using some Fungonil. The disease occurrence has been increasing steadily and I would like to eliminate using that plot for some time and try to increase the health of the soil and decrease the incidence of fungal diseases. What are my options?

A: These are my suggestions:

  1. Your idea of giving the garden plot a rest is a good one. I suggest you have your soil tested if you have not done that recently, so that you can find out the pH, level of essential nutrients, and organic matter content. You may need to make some adjustments with soil amendments, and taking a season to do that is a good idea.
  2. Next season, it would be a good idea to grow a cover crop (or two or three) in your garden plot. Cover crops build soil organic matter, improve soil structure and strengthen biological activity in your soil. All good things for healthy vegetable production. Here is a bulletin on cover cropping that is geared for farmers, but the principles also apply to gardeners, Cover Cropping for Success.
  3. You’ve done the right thing in removing and disposing of diseased foliage when you see it. Plant diseases often develop when we have rainy or humid conditions. Most fungal diseases spread more rapidly when plant leaves remain wet for a sustained period. These are additional good practices for disease prevention:
    • Consider spacing your plants a little farther apart for good air circulation.
    • If you use overhead watering, water only in the morning so that the leaves will dry during the day. Try to avoid wet leaves overnight. Consider using soaker hoses for drip irrigation. These target the plants’ root systems and keep the foliage dry.
    • Continue rotating your crops annually.
    • Look for disease-resistant varieties of vegetables in seed catalogs.
    • If you have a diseased plant, you can submit a plant sample to our diagnostic lab in Orono. Our plant pathologist will do her best to diagnose the problem and give you recommendations for treatment. Preventing diseases from developing is a better strategy, as once a plant is infected and shows disease symptoms, it can be very hard to contain the problem.

apples on treeQ: My son received two apple trees for a wedding gift. He is ready to plant them. Any tips for fall planting new apple trees? We live in Fort Kent, Maine.

A: Your son should plant the trees as soon as possible, in hopes that they will put on some root growth and anchor themselves in the ground before the soil freezes. Select a full sun site with good air flow. Avoid areas surrounded by dense woodlots and low spots. Fruit trees need a minimum of 18″ of soil depth. The soil should be well-drained, with a pH between 6.0 and 7.0. If your son hasn’t had his soil tested, it is worth doing. Here is our website on how to have your soil tested, Analytical Lab and Maine Soil Testing Service.

Please review the detailed recommendations on planting fruit trees in Maine at our website, Tree Fruits.

Q: I actually have three questions, pertaining to my garden bed.

  1. What is the best pH to grow yellow-eyed beans?
  2. How/where can I obtain a test kit to check the pH in my garden?
  3. Is it okay to plan anything where potatoes were attacked by scab?

A: Please see below.

  1. The pH for yellow eyed beans should be between 6.0 and 6.8.
  2. Get a Maine Soil Testing Service container and information form from your University of Maine Cooperative Extension County Office, or from the Analytical Lab and Maine Soil Testing Service. or call 207.581.3591. Some garden centers may carry them as well. See Fact sheet, Know your soil, testing your soil.
  3. The best way to reduce the possibility of potato scab is to purchase scab-free seed and to use scab treatments and to employ crop rotation techniques in heavily infested planting areas.

Recommended Disease-control Strategies from the University of Cornell

  1. Use resistant varieties in fields where scab is a problem
  2. Use scab-free seed and seed treatments to prevent the introduction of the pathogen into fields. Seed treatments do not eliminate the pathogen but will provide some suppression of disease. Consult current potato disease-control recommendations for appropriate seed treatments.
  3. Rotate heavily infested fields away from potatoes and alternate hosts such as radish, beets, and carrots. Use small grains, corn, or alfalfa in rotations; avoid red clover.
  4. Maintain soil pH levels between 5.0 and 5.2 by using acid-producing fertilizers such as ammonium sulfate. Avoid or limit the use of such alkaline-producing amendments as lime and manure.
  5. Avoid moisture stress during the 2 to 6 weeks following tuberization.

Here is a listing of fact sheets and bulletins from Cornell University regarding Potatoes, as well as this informative fact sheet from UMaine Cooperative Extension: Potato facts, growing potatoes in the home garden.

Killarney raspberriesQ: About half of our raspberries are not producing berries, sometimes producing blighted blossoms. The raspberries are on their second or third year since planting. Any advice?

A: The University of Maine has several wonderful fact sheets and videos on the topic of growing raspberries here in Maine. I am including those links in this response. Growing raspberries and blackberries in Maine.
There are several reasons why your berries may not be producing. Please refer to the sections on site selection and preparing the soil. The blossoms may be affected to poor air circulation and improper spacing or pruning. This is also covered in the publication above. If you think that you have followed the guidelines and your raspberries still do not produce next season, you may want to send a sample to the UMaine Plant Disease Diagnostic Laboratory, How to send a plant sample.

Q: I am planning on landscaping around a new house in Mount Desert using native trees, shrubs, and flowers. The fill is all sand and loose stone, and I will need a lot of topsoil, about 46 yards, for a 1,000-square-foot area. Can you recommend a local source for good, clean topsoil?

A: Buying topsoil (also referred to as loam) is a long-term investment, and I recommend that you visit contractors to have a look at (and feel and smell) their product before making a decision. The quality of topsoil can vary from batch to batch, depending on its place of origin, whether or not it has been screened, whether it has been blended with other materials, and how long it has been sitting on site. Many local suppliers amend the soil with composted municipal solid waste, which can have an unpleasant odor initially. Here is a link to a bulletin from the University of New Hampshire that explains what to look for and what questions to ask when buying loam: Purchasing Topsoil (PDF)
and another helpful brief bulletin from Michigan State University: The Shocking Truth About Topsoil.
Ideally, the supplier will have had the loam tested and can show you the results. If not, you can have a small sample of it tested for pH, nutrient content, organic matter content and lead level through the Analytical Lab and Maine Soil Testing Service at the University of Maine in Orono. I would be happy to help you interpret the results.
You can purchase screened loam from many landscape suppliers and general contractors found in the yellow pages.

Q: I have a bank of hydrangeas next to the house in Ellsworth. They now look dead and are a bit unsightly, so I started cutting the stalks and found that they are green at the bottom. Should I continue to cut them or should I wait until spring?

A: Pruning time and method of hydrangea are based on what type of Hydrangea you have. Plants that bloom on old wood should be pruned in the Summer after flower bloom. These include Hydrangea macrophylla and the Oakleaf hydrangea (H. quercifolia). They all produce blooms on old wood.

New wood bloomers can be pruned to the ground in the Fall. These include PeeGee types (H. paniculata) and the Annabelle types (H. arborescence). The one exception is the variety “Endless Summer.”

Here are some publications that will help guide you based upon the type of hydrangea you have.

Q: I recently purchased a Sunsation Magnolia tree for my front yard. The spot that I have picked out is perfect for its soil, sun, and water needs. However, after buying it, a friend cautioned me about planting it because the roots spread too much and could affect my home and the neighbor’s driveway.

When I did some research, I did find that the roots of the magnolia tree spread a lot, but also that they can be planted in pots, which seemed contradictory. Additionally, the information that I found seemed to reference the very large traditional magnolia trees of the south and not the smaller variety that I purchased. My questions are: Is root spread something that I should be concerned about with this particular variety? What advice can you give to me for successful planting?

A: Magnolia ‘Sunsation’ is listed as a plant that can grow up to 25’ tall and at least one nursery listed up to 15’-18’ width. This tree would best be planted at least that distance from any structure. Trees grown immediately next to structures can cause hazardous conditions for both the structure and the tree. Here is a link from the Morton Arboretum about tree root problems.

Most Magnolias extend their root systems up to four times the canopy width. This cultivar is listed as a possible container tree and street tree, so it may have a smaller root system, but it is still potentially a problem when planted too near structures.

This plant is listed as Zone 5b; USDA planting zone of Maine. Please make sure your location is within this zone. USDA plant profile magnolia (PDF)

Q: In our garden, we have a weed that wants to take over the soil and I can’t figure out what it is. I’ve attached a photo of it. Do I need to try to just control it by weeding continually or is there a better way to deal with it?

A: The weed pictured is Marchantia polymorpha. The common name is Liverwort. This is a common weed of excessively moist soils as well as rocks and tree bark. Liverworts require moister conditions than mosses. It is found in virtually every state and province in North America. The best way to eradicate the plant would be to somehow decrease the amount of moisture this garden receives. If it is in a rain garden you may wish to keep it as another fine example of a native plant species. Liverwort is usually only considered a nuisance in commercial greenhouse settings. The USDA had profiled Marchantia polymorpha as a plant of the week. Marchantia – Plant of the Week

Q: I am preparing a pamphlet of roadside native plants for a pesticide training class this fall. In researching Arrowwood Viburnum I encountered V. dentatum and V. recognitum as two different species. I want to use the Smooth Arrowwood (Northern) in the presentation but there is some confusion as to actual taxonomy. Some sites (Like GoBotany) have the Smooth variety as dentatum. Is there any real difference between them and what is the correct name for each?

A: The two Viburnums you mention, dentatum and recognitum appear to be the same plant. The confusion comes in with the common names, which are often interchangeable between species. The Lady Bird Johnson Wildflower Center at the University of Texas Austin lists synonyms for V. recognitum and V. Dentatum is one of those synonyms. Both are called Arrowwood and oddly enough V. recognitum also lists the common names of Southern Arrowwood and Northern Arrowwood. It would probably be best to use dentatum in your publication, as this is the commonly used species in Maine. Here is more information.

Q: I want to save my beautiful tuberous begonias and plant them again next spring. What process do you recommend for wintering begonias?

A: Carefully dig up the tuberous begonias within a few days of a killing frost. Leave a small amount of soil around each tuber. Cut off the stems about 1 inch above the tubers. Place the tubers in a cool, dry area to cure for 2 to 3 weeks. After curing, shake off the remaining soil. Place a layer of peat moss, vermiculite, or sawdust in a small cardboard box. Lay the tubers on the storage medium, then cover the tubers with additional peat, vermiculite, or sawdust. Store the tubers in an area with a temperature of 40 to 50 degrees Fahrenheit. Do not allow the tubers to freeze.

Q: We have two very old apple trees, 50+ years! One bears fruit but the other doesn’t. They are very close together with branches touching & some intertwined. Should we cut the non-bearing tree down? When is the best time to prune apple trees?

A: Apple trees can live for quite a long time, beyond 50 years. This does not necessarily mean that they will continue to produce fruit. Many apple trees do not produce fruit each year, sometimes skipping 3-4 years between fruiting. There are many variables that could play into why your fruit tree did not produce apples this year; drought or water stress, lack of available nutrients or just needing to take a year off. You should consider getting the soil tested. If it is a beloved tree then I would first recommend a rejuvenating pruning.

Apple Tree BorerQ: We detected a border ten days ago in one of our four apple trees. I removed it and the surrounding tissue at that time. Now all four have an active insect on the trunk near ground level. Please advise what can be done.

A: Have you seen the holes of the boring insect? If the holes are small you may take a sharp knife and locate the pest and kill them with a sharp wire. It sounds as if you have had partial success with this. Is there a reddish-brown frass below the borer’s hole? This would indicate continued presence of the insect.

If the whitish insects are indeed the white apple leafhopper, the spray you used was probably not effective as that particular pest is not included on the label. This pest has shown resistance to insecticidal soaps.
This pest affects the leaves of apples and will not go under the bark.

The best time to monitor for this pest is bloom – petal drop. See, University of Kentucky white apple leafhopper.

To help deter the boring insect from laying its eggs on the apple tree, apply a 50:50 mixture of white latex (not acrylic) paint and water as a thick whitewash to the lower trunk. The whitewash deters egg laying, and makes it easier to see frass from infestations that do occur. For more information check out, UMaine Cooperative Extension’s, Roundheaded Apple Tree Borer.

Q: I ordered Blue Lake Stringless Pole Beans and the supplier sent a substitute, Kentucky Wonder Pole Beans. I didn’t care for them and gave two pickings to neighbors. Now I have a third picking ready for harvest with most of the beans at full maturity. I am thinking of picking them and taking the beans out of the shell and drying them. I have never tried drying beans. What advice can you give me?

A: Beans are good choices for seed saving. They have flowers that are self-pollinating and seeds that require little or no special treatment before storage. Kentucky Blue Wonder Beans are not bred to develop the hard outer shell or the meaty insides that you’ll find with shelling-type beans. This does not necessarily mean they cannot be dried.

Saving the seed: Near the end of the growing season, allow the over-mature beans to dry completely on the vine. This may be as long as a month after you would normally harvest the peas or beans to eat. The pods will be light brown, and the seeds will rattle inside. Remove the seeds from the pods. After the seeds are completely dry, store Kentucky Wonder garden bean seeds in a cool, dry place for up to a year.

For complete instructions on how to harvest, store and save these seeds, please refer to this publication from the University of Minnesota, Saving Seeds.

Q: I’ve just finished building a cabin, and want to improve the soil this fall for gardening next spring. Problem is, the fill around the cabin is all sand and stones and it’s at least a couple of feet deep.
I need to bring in some topsoil. But I’m wondering whether I should first bring in some clay to form a base for the topsoil. I’m worried that if I don’t, the topsoil will leach through the sand and I’ll be back where I started. What do you recommend?

A: No clay is necessary. That would form an impermeable barrier and lead to drainage problems. A better strategy would be to “feather in” a 2″ layer of high-quality topsoil with the existing fill to create a transition zone, then spread high-quality topsoil over that and rake it evenly across the entire area. High-quality topsoil is well-drained loam without herbicide residue and with minimal weed seeds. Spread a minimum of 4″-6″ of topsoil for lawn, and up to 12″ of topsoil for other plantings.

Q: I have 16 raised beds, each 12′ by 4′. My paths between the beds are a little too narrow. I am having an issue with white mold. I noticed it a few years ago with my bean plants and each year I’ve planted my beans further apart (6″ in now), and I rotate my vegetables. I decided not to plant beans next year in hopes of getting rid of this problem, but I just noticed white mold in my lettuce beds (I let the lettuce bolt, so I can collect seeds). I don’t use herbicides or pesticides. And maybe I’ve put some diseased plant material in my compost. Any suggestions as to what I can do and still use my garden beds next year?

A: White mold is a fungal disease of vegetables that thrives in our cool, moist spring gardening conditions. The plants that are most susceptible to this disease are beans, tomatoes, potatoes, and plants in the broccoli family. You were right to increase the space between your plants to improve air circulation. The bad news is that this fungus overwinters in the soil as resting structures called sclerotia that can persist there for 5-8 years. Here is a link to a UMass Extension bulletin that explains the disease in more detail, and offers suggestions for cultural controls and prevention: White Mold on Vegetables

Q: Online information offers conflicting advice on how to prepare a Butterfly Bush for winter. It was planted this spring and we’re wondering if we should cut it back as well as protect the crown with some cover?

A: For butterfly bush, a thick layer of mulch is recommended to protect the roots in winter. According to UNH, Putting the Garden to Bed, “at least two inches of woodchips, shredded leaves, or straw should be applied over the root zone, taking care not to pile mulch against the plant’s trunks and crowns.” Additionally, Cornell’s Q & A does not recommend cutting stems in fall but instead waiting until spring.

garlic; photo by Edwin RemsbergQ: I live in Kennebunkport. When should I plant garlic and what type should I plant? Does it need full sun?

A: For your area, plant garlic from mid to late October, in full sun. Generally, hardneck garlic is grown in Maine, some popular varieties are Music and German Extra Hardy. For more information on how to grow garlic, see Bulletin #2063, Growing Hardneck Garlic in Your Maine Garden.

Q: Our house is surrounded by woods. We have several oak and maple trees which shed their leaves on our lawn. Is it ok to go over the leaves with a lawnmower to cut them up and then leave the pieces on the lawn?

A: You can certainly mulch leaves with a lawnmower and leave them, provided the leaf layer isn’t too thick. This may require mowing several times and is a good way to return organic matter to the soil. Leaving unmulched leaves is not recommended if you want to maintain a healthy lawn. This page provides a more in-depth explanation.

Blister beetleQ: Yesterday I found American Oil Beetles grazing on the remains of the tops of my potato patch. I have never noticed these in five-plus years of gardening on our property. What do you recommend as a course of action? There are about 12 to 18 beetles still present this morning.

A: American Oil Beetles are in the family Meloidae, also known as blister beetles. The name derives from a defense mechanism that allows them to release cantharidin, a chemical that can cause blisters. If you haven’t harvested potatoes yet, you could remove the beetles (cautiously, with gloves) although it is unlikely they would do any significant damage this late in the season. If you have already harvested your potatoes and they aren’t damaging anything else, they can be ignored.

Q: Our Betula nigra is seven years old, the tripartite trunk is spreading in three different directions. We question how to cinch the trunks to prevent damage to our home?

A: This page, My Minnesota Woods from the University of Minnesota, illustrates some staking and “guying” techniques for smaller trees while this one, Cabling, Bracing and Other Support Systems for Trees (PDF), illustrates support system options for larger trees. However, if the tree is large you should consult a licensed arborist for advice. Here is a list of Licensed Arborists in Maine.

Q: I just found Tectaria zeilanica or oak leaf fern growing in my yard. Is it hardy in Camden? How can I move it safely? Is it invasive?

A: Tectaria zeilanica (or Quercifilix zeilanica) is native to Asia and is a surprising plant to find here. If you have photos (ideally multiple angles and including photos of the spore structures) I could confirm the ID. You could also bring a sample to your closet Cooperative Extension office which I believe would be the Knox-Lincoln one in Waldoboro

Q: I have trees with leaves that look like maple leaves but with less fringe. It does turn color in the fall, but has blue berries and seems to be invasive. Do you have an idea on what tree this is?

A: Mapleleaf viburnum (Viburnum acerifolium) has bluish/black berries but is more of a shrub. Could that be it? If you could send photos of the plant (one that shows the whole plant and one that shows closeup detail of the leaves and berries) that would be helpful for identification.

Q: I am an educator at Deering HS, Special Ed. We received a grant to buy a grow table and lights. Every spring we start vegetables from seeds. This year we would like to grow things over the winter, both vegetables and flowers. Do you have any suggestions for vegetables and flowers that we can grow under the lights and that would produce vegetables and flowers?

A: This great publication, Organizing a Classroom Grow Station (PDF) from Cornell has some good info on seed starting, including the following list of plants: “Six easy to grow plants from seed, that you can explore in class without having to transplant to a larger space: radish, beets, nasturtium, bean, lettuce, peas.”

You may also find Bulletin #2751, Starting Seeds at Home helpful as well as our video, How to Build a Seedling Stand to Extend the Gardening Season and instructions (PDF). This publication from Iowa, How to Succeed at Seed Starting (PDF), also has some great tips, including how close the light needs to be to the seedlings, hanging the lights too far away is a common mistake!

Lastly, Pamela Hargest, the Home Horticulture Professional for Cumberland County may also be a good resource for you. Her contact info can be found here.

Q: Some pine firelogs in my woodshed are apparently being consumed by worms or ants. Should I dispose of them before the pests migrate to my shed or wood supply? The spoils resemble worms but appear to be wooden residue.

A: There are a few possible culprits that could be eating your wood: carpenter ants, termites, or several kinds of beetles. The two that can be problematic for wood structures are carpenter ants and termites. The chance of carpenter ants brought in on firewood establishing a nest in your house is low, although it is not recommended you stack the wood against your house. Termites brought into your house on firewood cannot establish a new nest because the queen lives in a nest in the soil. The best way to avoid termites is to stack wood off the ground. It will generally take insects several days in a warm house before they become active. Don’t bring in firewood more than a few days ahead of time.

If you would like to identify the insects you could attempt to pull off bark or dig into a log to find some and send them to our insect lab for ID. Follow directions for packaging and complete this form.

It is not recommended to spray any insecticides on firewood since they are unlikely to penetrate deeply enough and could pose a health hazard once brought inside.

Here are two publications that have more info on the possible culprits: Insects in Firewood and Insects and Firewood (PDF).

The fruits of American cranberrybush viburnum (Viburnum opulus var. americanum) add a splash of color to the bayberry hedge.
The fruits of American cranberrybush viburnum (Viburnum opulus var. americanum) add a splash of color to the bayberry hedge. Photo by Reeser Manley.

Q: I am interested in planting a line of hedges, as a divider for playing fields at a children’s summer camp. I envision something manicured like boxwood, that would grow fast like privet. I see that privet is an invasive species, not permitted in Maine. Could you please give me some options that would be sturdy and grow fast?

A: The decision about what to plant to form a hedge is dependent on a lot of factors:

  • Do you want things/kids to cut through or do you want to use this to keep them out of adjacent areas?
  • How high do you want them to be and do you want them to be evergreen or deciduous?
  • How big is the area?
  • Do you want them to all be the same like a wall or more natural-looking?

Here are some taller, slimmer shrubs that form a hedge fairly quickly:

  • Columnar Juniper like “Taylor” planted closely together, these are prickly so they make good barriers.
  • Arborvitae and Yews are both classic hedges but also like candy to Deer so I don’t recommend them.
  • Cotoneaster is another fairly formal option

For more naturalistic hedges:

  • Forsythia can make a nice hedge and grown pretty quickly. They will need trimming each year after they bloom to keep them compact and dense. They flower before camp starts so bees should not be an issue.
  • Arctic Willow (PDF) makes a very fast grown hedge but it is more naturalistic. It can be trimmed back severely each season to keep it to the height and width you want.
  • Some Viburnums (PDF) can become beautiful hedges but they do flower in the summer so bees might be an issue.

Q: I am interested in identifying wild mushrooms, which ones are edible and those that are poisonous, etc. What resources do you have that could help me out?

A: The UMaine Extension does not have a mycologist on staff. The University has an education professional who focuses on fungi and the UMaine Extension has a plant pathologist on staff who studies fungi: Maine Food and Agriculture Center.

I am assuming you are looking for edible mushrooms. In many areas there are adult ed “Mushroom” or Foraging Walks offered in spring and fall when there is a higher likelihood of finding mushrooms. You can contact the North America Mycological Association for mushroom clubs in your area. They would also be the resource of who the experts are in the area.

late blight on tomatoes
Tomato plants infected with late blight.

Q: Late blight on my tomatoes has spread to my potato plants. I have removed the tomato plants and potato tops. Tubers do not appear to be infected. Should I dig them ASAP, or let them stay in the dirt longer? One source I read said to leave them to give the spores time to die down, and another said to harvest them so they don’t spend any more time in possibly infected soil. Thank you for any advice you can give. I am taking other steps to manage and contain the blight, but am really hoping to be able to save some of my potato crop.

A: Late blight is a very serious disease and it can affect more than your garden/farm if the spores go airborne. Here is a short video that shows how to identify late blight in both plants. Tomatoes are subject to so many blights it is a hard call but this video is a great refresher on the symptoms in both plants. The answer to your question is actually in the bulletin about Gardening After Late Blight (PDF). If you are removing the tops of the potatoes completely there is no reason to leave the potatoes themselves in the ground. They will not continue to grow and it also increases the chance that small potatoes might be left in over the winter, come up in spring, and carry blight into the next season. If you are able to contain the blight and have leaves on your potatoes then keep them in the ground as long as you can.

Q: I have a small 2′ x18′ foot long flower garden in front of my house. The last few years flowers have not been growing. I did a soil test and found out the soil is sandy clay, depleted of Nitrogen, and deficient in Potash. PH was 7 neutral. What would be the best way to improve the soil? Not sure if I should add compost or fertilizer to the soil. Also, should I try to get more acid in the soil?

A: Did you do the soil test with the UMaine Extension? If so, there are recommendations in the center of the report and your county Extension agriculture or horticulture professional can help interpret those test results. Interpreting Soil Test Results for Gardens and Grounds explains the things to look for. If you tested elsewhere, then there are several general things to address and fall is a great time to address them.

Let’s start with pH. Even though 7 is neutral, most plants like the pH on the acid side, between 5.8 and 6.8. Your soil is actually a little too basic for the cation exchange process to be optimal. If you have been liming the soil, don’t do it this fall. If there is the opportunity to add sulfur, that might help but without exact info from a soil test I can’t really tell you how much to get you into the 6.3-6.6 range.

Soil tests are unable to measure nitrogen accurately in most garden tests because nitrogen moves around in the soil so much. If your test results show a depleted soil, then fertilization will be necessary every year. Perennials only have to be fertilized in the spring and annuals get two applications, one late spring and one early summer. Sandy soil will make leaching more likely also, so try to make sure you fertilize after a good rain not before. Did the test measure OM (Organic Matter)? That is always something you can add to help the soil build not only fertility but more importantly good soil texture. Good soil texture will allow for better holding of water and nutrients. If the clay you have is like a hardpan then the OM will hold the water before that gets mucky.

Without the specifics of a test, it is impossible to give specific recommendations on fertilizers. Potash/Potassium is the third number in that series of three on the front of a fertilizer bag. Make sure you are using a complete fertilizer (Nitrogen, Phosphorus, and Potassium). I recommend you do a soil test that also gives recommendations based specifically on your soil. You can get the test kit from any UMaine Extension office. You pay for the test when you send it in and there are slight discounts in the winter. This test would also cover micronutrients needed for good soil and plant health as well as pH, macronutrients, organic matter, and lead testing. The test can be done any time of the year but if you do it now you can use the fall and winter to let things really get mixed in thoroughly. Lastly, check for compaction in the soil. If this is an area that has snow piled on it all winter that could be compacting the soil so the plant roots have a hard time getting a fast start after transplanting.

If the soil is compacted, an option is to build soil on top of the existing garden, if there are no perennials there. This can be done using a technique called Lasagna gardening. A bulletin from Oregon State covers this well. It has the added benefit of smothering the perennial weed seeds and also making it easy to address the annual weed seeds in the top of your soil. Really good gardens often have built up 6, 8, even 10 inches of soil by adding some compost, organic matter, soil amendments, etc., each year. Then the plants are living primarily in the soil you made, not the soil that the builder put there when the house was built. Remember we have had unusual weather the last few years: drought and too much rain, depending on the year. Good soil will help even out the ups and downs of the weather a lot. Best of luck getting that garden back to its former glory.

Q: I have a 10′ x 20′ patch of freshly disturbed, bare soil in a shady part of my yard. Is there anything I could plant in it from seed that would grow before winter and hopefully keep it from turning into a big mud pit in spring?

A: There are a couple of ways to approach this depending on the final destiny of that plot of land.

If you are going to be planting seeds next year, I would normally recommend you plant a cover crop of something that can then be dug into the soil in the spring (like mini clover or red clover). The problem is that we are getting to the point that not only are you in the shade but also the days are short. Establishing the ground cover this late in the year means the weeds are also going to get a foothold. If planting seeds is the goal, then I suggest tarping or “sheet mulching” the area, and then it will be ready to plant first thing in the spring and will not end up being muddy.

If you are looking to eventually plant seedlings, a few shrubs, perennials or ground covers, then I suggest you can actually get anything hardy into the ground now, otherwise cover the area with 8 sheets of overlapping newspaper and top it with mulch. The newsprint will degrade and a shredded bark mulch will actually add to the organic matter in the soil.

If you are not sure what will go there next, then I recommend you just put clear plastic on it and weigh it down with rocks. You will get weeds growing under the plastic in a couple of weeks. Lift the plastic, hoe or mow the weeds, and leave them on the soil to degrade. Cover with plastic again and do the mowing again if we have enough sun and time for more weeds. Do that one more time in the spring and you will find that you have depleted that patch of all the weed seeds in the top layers of soil. Come spring you will have a clear patch to start a new project in.

black row coverQ: I have heard that to kill the weed seeds sitting in the soil, you could “cook” the soil under black plastic. If that is true, for how long & when?

A: It is true that weed seeds can be killed by getting them to a high temperature. We call it solarization of the soil. It can be done with black or clear plastic and has to be done when the days are near their longest. May, June, and July are best, though some start early and leave it later.

If you are using plastic, the solarization process will actually go more quickly as the soil will heat up faster and get hotter more quickly. The article Solarization in the Garden from the University of Minnesota discusses this process.

Since you asked this question in the fall, there is another option for you. If you do some sheet mulching or “lasagna” garden preparation in the fall, you will start the spring with all your perennial weed seeds buried under many inches of good growing media. As long as you don’t till the soil in the spring but rather plant into the soil you created, those weed seeds will not bother your garden. Some perennial weeds may not be as easy to control with this method. Japanese Knotweed, Bittersweet, and Horsetail just to name a few. If you are in the area there is actually a sheet mulching talk and demo in Androscoggin County next week.

Rosa RugosaQ: Can you please tell me what these are? I saw them growing along Marginal Way in Ogunquit.

A: The plants that you are seeing along Marginal Way are Rosa Rugosa. These are also known as sea roses or salt spray roses. See this Beach Rose Fact Sheet for more information. The orange “berries” are the rose hips, which are the seed pods of the fertilized blossoms. Rosa Rugosa is a rapidly spreading plant and is considered invasive in some states; it is on the Maine Invasive advisory list. In the northeast, this plant is also seen as a way to restore natural (not native) habits in some problematic areas like roadsides. It is also seen as an indicator species in the area of phenology.

gourdQ: I’m growing ornamental gourds and wonder what’s the best way to dry them? Also, I was told that bottleneck gourds do just fine leaving them right in the garden to dry.

A: If you have ever grown winter squash you will find this process very familiar. I am referring to the information in this bulletin, Gourd Success Includes Proper Harvesting & Handling, from the University of Illinois Extension. To get gourds that last, you will need to cure them both inside and out and also do it once they are ripe but before there is a frost. Although the different types of gourds are handled slightly differently, all depend on timely harvest, proper cleaning, and proper curing.

Make sure the squash is fully ripe; a hard shell and withering vines are good clues. Wash dirty gourds in soap and water and rinse in a weak bleach solution: 1 part bleach to 15 parts water. Then cure according to the directions in the bulletin cited above.

Q: I live in Deer Isle, and would like to get some milkweed seeds to plant this Fall. Where can I purchase these seeds, and how much do they cost?

Monarch butterfly on Asclepias incarnata
Monarch butterfly on Asclepias incarnata, our native swamp milkweed. Photo by Reeser Manley.

A: I am glad you are thinking about this a little bit ahead of time because once they are ready they go quickly. How one family goes about collecting and dispersing the seed is outlined in this Milkweed Seeds article from MOFGA.

An article from the Xerces Society called Harvesting Milkweed Seed: a Pod and a Plan contains great background information. In Maine, the Wild Seed Project is a good resource for info and advice on where to find the native milkweed seed. Locally you may be able to find a local land trust that is aware of where wild milkweed grows and you can get pods there (with their permission of course). Lastly, you can also go online and buy seed (just search for the seed by the botanical name so you get varieties suited to Maine). Don’t forget to also plant some nectar plants for the adult Monarchs too; consider it the local craft drink for the adults getting ready to migrate.

Q: I moved into a new house in Kennebunk, Maine, last fall. I have been struggling to figure out how to maintain all of the trees and shrubs we now have, when to prune, how much to prune, etc., but my more immediate concern is with a mature peach tree. The tree seemed to be growing fine all spring and summer. It had an abundance of peach fruits on it, which we thought should have been growing a lot more than they were. We did a little research and found out that we should have thinned out the peach population to about one every 6 inches or so. So we did a little bit of thinning a couple of weeks ago and a few minor pruning cuts as well and it seems that the tree has gone downhill since then. The leaves began to turn yellow and now they are turning brown and the tree just kind of looks wilted. I don’t see any specific lesions or spots on the leaves and the apple tree right next to it seems perfectly fine, so I would be challenged to think it was simply lack of water. Do you have any ideas on what it could be and what might be done if anything to preserve the tree? I should mention that I work for Syngenta and am familiar with fungicidal applications if one were necessary, but obviously I need to figure out what is going on first.

There does seem to be a significant crack in the trunk, with some minor oozing at the top. There’s some possible woodpecker feeding on one branch opposite the crack (this branch has ironically kept most of its leaves so far), and nothing really notable at base of trunk except perhaps that the grass is right up to the base and there’s an odd indent/narrowing at the base.

A: The problem could be Verticillium wilt, a soil-borne disease that can affect a wide variety of plants. I have shared your images with our tree fruit specialist, who does not think the problem is winter injury or general decline. If you can get a sample to UMaine Extension’s Plant Disease Diagnostic Lab in Orono, they can see if they can culture anything out for you. Here are the instructions. The sample should be a branch or two that has dying (but not dead) leaves. I have already shared your photos with the lab diagnostician.

Q: I had a question about an outdoor succulent called Chicks and Hens (Sempervivum tectorum). We have a few potted in large ceramic planters and want to learn how to best overwinter them in central Maine. I have read that when in the ground, they are hardy to Zone 3, but I’m not sure about potted plants. Can you advise us on the best method for overwintering these potted plants?

potted succulentsA: You definitely have options depending on the size of your pots. Sempervivums, though evergreen, do go dormant over the winter, so if you choose to bring them in, make sure you have a consistently cold place to keep them as you don’t want them going in and out of dormancy. They are hardy to Zone 3. Outdoor temperature is not really as much of an issue for the plant as it is for the container and the plant’s roots. Ceramic pots can take cold and heat, but they don’t do well with the change from cold to hot. It is a phenomenon called heaving and you actually see that in our roads in the late winter/spring. It is when the moisture in the soil expands and contracts and at some point the pot will likely crack and also heave the roots right out of the pot.

If your pots are heavy and you don’t want to move them indoors, then you should wrap them in place for the winter. This bulletin from the University of Nebraska addresses wrapping potted trees but the advice would apply to sempervivum also. If the pots are smaller and you bring them into an unheated porch or garage, there is little that you need to do besides keeping them out of direct light. Very small pots (such as starter plants) should go into the house and be treated like a houseplant all winter. As the days lengthen in March and temperatures fluctuate less, then you can bring them outdoors into a protected area to get re-acclimated. Keep them out of direct sun and winds until the temperatures are regularly above freezing night and day, probably early May in central Maine.

Q: A friend told me that you have a list of when is best to transplant different plants. If so, how do I get it?

A: For edible crops, you’ll find planting dates on the last column of this planting chart and also some great information on this resource from MOFGA.

There’s a nice spreadsheet on when to divide and transplant specific perennials linked at the bottom of this helpful bulletin.

Q: What is the best grass to plant around fruit trees? We are starting a small orchard in Oakland and we’d like as little mowing as possible.

apple trees in blossom at Highmoor FarmA: There are several considerations for the different areas within an orchard. The two big ones to focus on are 1) the tree row area and 2) the between-rows area. One size might not fit all, especially in a newly planted area. One consideration for the tree row area is to not allow grass or weeds right up next to the new trees. Young trees don’t want competition for water or nutrients. Taller grasses and weeds will also harbor rodents in the winter that could girdle the tree. In a newly established planting, mulching this area is actually the best way to avoid problems.

If the trees are well established, then turf between the trees in the tree row area should be a shade tolerant, low mow type grass, however, whatever is planted there will always compete with your trees for water and nutrients. See this University of PA Orchard Establishment bulletin.

A traditional way to establish plantings between the rows of trees is to plant turf that has the characteristics of low-frequency of mowing, low legume plants, and durability. A mix that has a high predominance of fescues (60-70%; about half and half creeping and tall) and some ryegrass, both annual and perennial, will fit the bill. As the trees grow and this area becomes shady, consider adding more of a tri-type rye that is also more durable as well as shade-tolerant, like that used on golfing fairways and parks.

If your orchard is going to be attractive to pollinators and birds, you may want to consider treating it like they do the sides of the highway and plant native grasses with the thought of mowing only a few times a year. Effective Establishment of Native Grasses on Roadsides in New England (PDF) from the University of Connecticut has some very interesting reading on that.

Q: Yellowjackets are building a nest in the siding of our house, right next to our back door. They seem to be oblivious to us and we haven’t gotten stung. We don’t want them there as we have a three-year-old. We called a pest control company and they said they could come out and put Tempo 1% dust in the hole that the hornets are using to access the house. We are hesitant to do this because, in general, we don’t like using toxic pesticides. Are there any less toxic alternatives that would take care of our problem? How harmful would this application of Tempo dust be to other bugs and animals in our yard/community?

A: A yellowjacket nest in the house, particularly near a door, can pose a significant risk of getting stung. We generally encourage people to leave the nests of stinging insects alone, but not in a case like this. The dust formulation is important here because it can be “puffed” into the area behind the siding and reach places that would be inaccessible by a liquid or foam. If you are interested in an organic option, you can ask your pest control company if there is an appropriately-labeled formulation of pyrethrin they can use. Keep in mind that pyrethrin will break down quickly and not provide much for residual activity.

The Signal Words (PDF) on a pesticide label (Caution, Warning, Danger/Poison) indicate its acute toxicity. The signal word “Caution” indicates relatively lower toxicity. For information about toxicity, you can check the product’s Safety Data Sheet, which can also be obtained from the manufacturer or found on their website. Additional information about active ingredients can be found at the National Pesticide Information Center.

All pesticides have a risk of off-site effects. Since the product would be placed under the surface of the siding, there would be less material released into the environment than if it were a broadcast spray. It is possible that the yellowjackets could carry the pesticide out of the nest and transfer it to other insects nearby. This will be true for any dust material used. Natural pyrethrin is still toxic to many insects. As with any pesticide use, you will need to balance the benefits of treatment with the potential off-site effects.

Q: We live part of the year in Sebago. I’m planning to convert a sunny hillside (with dry soil) to a wildflower and perennial garden. Is September a good time to start sowing wildflower seeds? We are here through October, so I would be able to water the bed for at least 6 weeks. Also, is it true that I can just leave the existing grass (well, really very low growing weeds and such) and sow seed among what’s there? I plan to order seeds online. Do you have suggestions of where to purchase the best seed for our location/soil?

wildflowersA: This is a tricky question because it all depends on what your expectations are and the level of work you want to put into it. Wildflower and perennial gardens can take a significant amount of work to establish and maintain if you’re looking to have a diverse collection of mostly showy flowers (i.e. very little to no grasses and “weedy” plants).

If you’re aiming for a more showy collection, you’ll want to spend some time establishing a clean slate by covering the area with plastic, tarps, or a layer of cardboard topped with mulch (more aesthetically pleasing) for a full season, removing the covering the following spring, then repeatedly cultivating the space shallowly over the course of several weeks as the weed seeds in the soil seed bank germinate in now fallow area. You could also establish a clean slate by removing the sod, but then you’re removing a layer of very useful organic matter that will benefit the wildflowers you’ll eventually plant in that area. If you take the first approach, the period in which you cover the area can be shorter, but perennial plants may not be sufficiently killed off if it’s not covered long enough. Once the prep is done, then the fun of seeding and planting can begin. Small plants (also known as plugs) or bare root plant material can be more affordable than using potted plants and are pretty easy to establish when planted in the spring when rainy weather is more likely. It’s always a good idea to plan on 1″ of water a week for any newly installed plants. Direct seeding for most native wildflowers is generally done at a time when the plants would naturally drop their seeds. How to Grow Natives From Seed includes listings of different types of germination requirements for various plant types.

With all that said, you can simply clear some small spaces in the area and sow seeds directly now. The long-term success rate for this approach is much lower and you’ll find that what’s there in your soil (existing plants and the seeds in your soil) may very likely out-compete what you try to introduce. A third option is to try a hybrid of both techniques or do the area in phases to reduce the initial expense and workload.

We are not permitted to endorse any specific companies, but it wouldn’t hurt to keep your sources to Maine or New England based vendors. These “local” vendors can often provide some excellent tips and customer support for folks in their own growing climate.

More info on the topic can be found here, Establishing Wildflower Habitat to Support Pollinators of Michigan Fruit Crops (PDF).

Q: I have black, sticky, crusty areas on some of my peaches. I have never used anything to treat them. My tree is huge and needs to be trimmed down as the peaches are smaller this year. Any advice would be great. Organic solutions, non-toxic, etc. Also, how do I maintain a peach tree in Maine?

ripe peaches on treeA: A great resource for you is UMaine Extension’s Growing Peaches in Maine. That should address your questions about maintenance. There are a variety of diseases that can affect peach fruit. I would suggest you send a sample to our Plant Disease Diagnostic Lab. If it is a disease, the pathologist there will be able to identify it.

Q: There is conflicting advice on when to prune magnolia soulangeana trees. What do you recommend?

A: We recommend that you prune these either in the late winter when they’re dormant or just after flowering. If you were to prune now (end of August), the tree might send out new shoots that won’t have enough time to develop winter-hardiness. You can prune dead twigs or branches any time.

Q: Can one make manure tea out of fresh chicken manure and safely pour into the garden next to the above-ground crops?

A: Even for manure tea, I recommend that you follow the raw (uncomposted) manure guidelines that are outlined in UMaine Extension’s publication, Guidelines for Manure Use on Vegetable Gardens. That recommends a waiting period of 120 days from time of application to harvest of plant parts that have the potential to touch the soil, such as leafy greens. For plants where the harvested part does not touch the ground, the National Organic Program has the guidance of a 90-day waiting period. Remember that soil particles and pathogens may be splashed onto plant parts that are above-ground.

Q: I have a Macoun apple tree, along with a small Cortland, and two crab apple. Every year the Macoun flowers, develops fruit, and they all drop off within the first month. Could you help me in determining what might be the problem? The tree is about 18 years old and has never fully developed apples.

A: There can be many reasons why an apple tree may fail to develop fruit. One is improper pollination. Macoun does need a different variety in order to be pollinated. As long as the Cortland (also a mid-spring bloomer) has a good set of flowers, it should be an adequate pollen source. This spring was cool and wet, so in some cases, pollinator activity was reduced, which could lead to early fruit drop. Insufficient carbohydrate production, such as during cool, cloudy weather, can lead to tree stress and fruit drop. Too much nitrogen fertilizer and over-pruning can also be causes of lack of fruitfulness. Later fruit drop may be the result of insect infestation of the fruit. UMaine Extension’s Growing Fruit Trees in Maine has a section on lack of fruitfulness in tree fruit, as well as other production information that may help you.

Q: This morning, I caught the tail end of a story about monitoring the migration on Monarch butterflies. Can you give me any information as to whom I can contact? As I have been raising Monarch butterflies for the past three years, and I have lots of pictures.

Monarch butterflyA: You probably heard part of a story about UMaine’s Monarch Model Validation Project. This is an opportunity to help scientists better understand where monarchs roost during their migrations. For more information read the UMaine News release.

Q: I planted Polona raspberry plants three years ago. I live in Franklin County in Salem, at the base of Mt. Abram. The plant source was a local nursery, whose employee suggested them. The raspberries never mature before the frost comes. I just read in a bulletin on raspberries that this variety may not mature if the plants are in colder areas, which I think my area, here in the western mountains, may be. I think I may have to rip these plants out and start over. What do you think of that idea and what variety would you suggest to replace them?

A: Polana is an ever-bearing raspberry, meaning that it will bloom and set fruit on first-year canes. Ever-bearing varieties are later-maturing than the biennial bearing varieties to begin with. The colder areas of Maine are usually too cold to allow even Polana to ripen. That could certainly include your location, especially if you are in a colder microclimate. Two earlier ripening, ever-bearing raspberries you might want to try are listed in this UMaine Cooperative Extension fact sheet Growing Raspberries and Blackberries:

  • August Red: Earliest ripening of everbearing types. Soft, medium-sized fruit with fair flavor. Short, spiny canes.
  • Autumn Bliss: Early ripening fall crop with large flavorful fruit. Canes are moderately vigorous with few thorns.

You might also want to consider growing summer-bearing (biennial bearing) raspberries, since they will mature earlier than the ever-bearing varieties.

While cold certainly does seem to be a likely suspect, in this case, you may want to review the maintenance instructions for raspberries, particularly light requirements, and fertilization, to be sure something else isn’t contributing.

Q: I have a parthenocarpic cucumber plant that is not producing any fruit. It has lots of male flowers, but the bases of the flowers won’t grow into cucumbers. Do you have any ideas on what could be happening?

A: There are a few reasons why your cucumber may be producing only male flowers. Hot weather, drought stress at flowering, drought stress early in plant development, and over-fertilization with nitrogen can either skew flower development to favor male flowers or lead to the abortion of female flowers. Also, the first flowers produced by the plant are usually male, with female flowers following later. If you are keeping the plant well-watered, there isn’t much you can do about the other conditions except wait. Luckily, our very hot temperatures seem to have passed, so that may help. More details about this problem can be found in this article from Iowa State University, Where are the Female Flowers?

Q: Two years ago we bought organically grown buttercup squash at a local farmers market. We saved and planted some seed last year with decent results. This year we planted more (now two-year-old) seed. This squash plant looks very much like butternut squash with only a few very small squash having the appearance of buttercup. Can you tell me why this is and if these squash will be alright to consume? Assuming they turn brown as they mature. They are now green in color. They are planted in raised beds and climb on a fence.

A: The answer starts with a basic botany lesson. Squash and other crops within the cucurbit family (cucumber, pumpkin, zucchini, gourds, melons, etc.) have separate male and female flowers on the same plant. The easiest way to tell the difference is the female flowers appear to have a small fruit (it’s actually the ovary) at the base of the flower. When pollen from the male flower is transferred to the female flower and the pollen successfully fertilizes the ovules within the ovary, the fruit will develop. Closely related plants within the same family can often develop fruit when pollen from one type happens to be deposited onto the female flowers of another type. The resulting fruit will look normal, but the seeds will carry the genes from the two different parents.

An analogy I like to share when teaching botany is with a female yellow lab and a male black lab. When the two labs breed, the female dog (analogous to the fruit) does not change color, but the puppies (analogous to the seeds) will have a mixture of traits from both parents. Some puppies will look like the mother, just like the plants and resulting fruit from some seeds will look like the fruit that you collected them from.

Q: I’m working on replacing my front lawn with a wildflower/prairie landscape. This is the first year. In the area I’ve planted (with a wildflower mix) there are some bare spots. Is it too late to plant some flowering perennials? Also, come fall, would you recommend I mow the plot to promote reseeding?

A: It’s not too late to plant in the bare spots. You can take two approaches: installing plants or direct seeding. Potted plants can be installed now, but you’ll need to provide about an inch of water a week to help them get established. Direct seeding for most natives is generally done at a time when the plants would naturally drop their seeds. Here’s a nice resource that includes listings of different types of germination requirements for various plant types. I typically rely on rain to help get the direct-seeded crops established.

The question of mowing is tricky because it depends on the weed pressure you have in the area and the types of insects you’d like to support. Some insects overwinter in plant debris and are destroyed when areas are mowed. A good compromise would be to mow most of the area in the fall, but leave a few strips for overwintering habitat. Alternate where you have those strips each year so you can ensure woody plants don’t get established.

Q: What are the brown beetles that are everywhere this year? I don’t remember seeing them in the past. They are about the size of a Japanese beetle.

A: Do you have a photo you could share and can you tell me more about what plants you’re seeing it on?

There are a lot of insects that match your description. One that comes to mind is the oriental beetle. Here’s a nice fact sheet that shows three very common brown beetles. Do you see something that matches what you have?

Killarney raspberriesQ: We have an old (20+ years) red raspberry patch that has lost vigor and is full of nonbearing black raspberry and other weeds. We have tried thinning and soil amendments. How does one restore an old patch like this?

A: A well-kept raspberry planting will produce fruit for 10 to 20 years. If your raspberry patch is 20+ years old, I’d recommend starting fresh with a new planting that will be easier to maintain from the start. You could try to rejuvenate your old raspberry patch, but it’s very likely it still won’t produce very much fruit and the process would be very labor-intensive.

For more information about growing raspberries in Maine, check out our Bulletin #2066, Growing Raspberries and Blackberries.

Q: My Japanese maple has died except for a few “sucker” branches at the bottom. Should I cut the dead stem and hope the suckers will take over? Or should I remove the suckers and try to root them?

A: Do you happen to know which cultivar of Japanese maple you planted? Japanese maples do best in zones 5-9, so it’s a good idea to plant a cultivar that is a little more tolerant of our harsh winters. Depending on where you live in Maine and the cultivar you planted, you may be better off starting fresh with a new cultivar of Japanese maple or going with a native tree or shrub that is more adapted to our climate.

Q: We own 86 wooded acres in Porter, Maine. There is a mix of softwoods and hardwoods on our land. We will be building a small home on the land in the fall. We do not want to plant grass around the house. We would prefer some other type of ground cover which would appear more natural in the wooded setting. Do you have any suggestions for us?

A: There are many options for your site, but here are a few to consider:

  • Barren Strawberry – Waldensteinia fragarioides (native), full sun/part shade
  • Bunchberry – Cornus canadensis (native), shade/part shade
  • Foamflower – Tiarella cordifolia (native), part shade
  • Partridge Berry – Mitchella repens (native), shade
  • Creeping Thyme – Thymus serpyllum, sun/part shade
  • Bearberry – Arctostaphyllos uva-ursi (native), full sun/part shade

For more information about groundcovers for the Maine landscape, check out our Groundcovers list in our Master Gardener Manual.

Q: I live in Westbrook but grew up in Ellsworth, where I always had wild blueberry bushes in my yard. I’d love for my kids to have wild blueberries around, too. Is it possible for me to plant wild blueberries around our property? Can they grow from the fruit, or only from a clone or graft of an existing bush? Any guidance you could offer would be much appreciated!

highbush blueberriesA: You can absolutely plant blueberries on your property! I’d recommend planting healthy 2- to 3-year-old plants from a nursery in your area. You could plant 1-year-old rooted cuttings, but they’ll grow very slowly and take longer to produce a large crop of fruit. You’ll also want to make sure you plant two or more varieties to ensure good pollination.

Select a site that has full sun and wind protection. Blueberries prefer well-drained, sandy loam soil that is rich in organic matter, so avoid areas of your property that have drainage issues. Blueberries require acidic soils (pH range 4.5 to 5.2) for good growth, so it’s important to have your soil tested before planting your blueberries. The soil test will also assess the fertility of your soil and give recommendations for any amendments you should add before planting.

You can pick up a soil test kit at your local UMaine Extension office in Falmouth or we can send you a soil test kit. When you go to fill out the form, make sure you select the appropriate crop code (Highbush Blueberries – To be planted).

For more information about growing blueberries, check out our Bulletin #2253, Growing Highbush Blueberries.

Q: Why do my tomato plants get little fruits that then fall off? We seem to have a lack of bees. Could that be the cause?

A: Yes, if the fruit aren’t pollinated, then they may drop, or the flowers themselves may drop. A lack of pollinators could be the cause, although wind can often be enough to pollinate tomatoes. Another possible culprit is the high temperatures from last weekend. Tomato pollen is less viable at high temperatures, and so pollination rate is much lower. This should turn around now that we’re having milder temperatures.

tall plant bent from heavy rainQ: A cluster of large stalks that have purple flowers that turn to pods are perennial in one of our gardens. (I don’t know what type of plant they are.) They usually grow straight up, but this year, after a particularly heavy summer rainstorm about two weeks ago, they became bent over and have not straightened out again. Some of the stalks are actually creased at the bend, others are just bowed. See the attached photo. Should I cut them back?

A: This plant looks like baptisia (Baptisia australis, false indigo). If possible, you should leave the plant to continue photosynthesizing and sending energy to the roots. Since it has already flopped over and may be getting in the way of some other plants, you could prune it back some — preferably not more than a third — to keep it out of the way. This will help reduce plant volume and weight. You could also consider staking or tying the pruned plants if they are still flopping over.

Q: There are no honeybees or bumblebees in my yard for the first time in my experience. I have a variety of flowers and bushes. I mow my lawn on the highest level so that the clover and other lawn plants are available for the bees. What do you think is happening? I use no pesticides in my gardens or on my lawn. I live in Lewiston.

A: Pollinator levels can vary each year, depending on local weather conditions. You’re already doing some of the important things for maintaining pollinator populations. More ideas can be found in UMaine Extension’s Understanding Native Bees, the Ggreat Pollinators: Enhancing Their Habitat in Maine. I have sent a note to our State Apiarist to see if there is anything else that might be going on, just to get her perspective, and will let you know what I find out.

Q: What could I use to stop ants from eating my carrot seeds after planting?

A: If you have a lot of ant activity in the area where you have planted carrots, they can definitely cause some problems, although they are not necessarily the problem in this case (see below). Ants’ extensive tunneling is good for the soil, but it really wreaks havoc on root systems by interfering with soil contact and allowing the roots to dry out. And, some species of ants can directly eat the seed or small plants. To manage ants in this area, you could consider pouring boiling water on the suspected nest entrances. This obviously requires considerable care and can be cumbersome. Multiple applications may be required, and success will depend on the actual location of the nest. You could consider getting some ant baits, being sure to find ones that are labeled for outdoor use and that are labeled for use in food crops. (Always remember to read and follow label directions for pesticides.) If you have the option, you could consider moving your carrot planting to a different area of the garden, one that has fewer ants.

However, ants may not be the problem. If the carrot seed isn’t germinating, it could be because the soil is too hot or too dry. Carrots are finicky even under good conditions, never mind when it’s hot and sunny. Frequent sprinkling with water (multiple times a day on sunny days), use of mulch (light sprinkling of straw), or using row cover can help. The ants may be innocent bystanders in this case.

Yellowing potato leafQ: I am growing potatoes and noticed that something seemed to have bitten off the tips of my blossoms on some of the plants. I suspected hornworm but could not find any. Nevertheless, I sprayed with Bt about 5 days ago. Today I notice more evidence of chomped off blossoms so maybe my problem is not hornworm, or maybe it takes longer for Bt to be effective? I’ve not used it before. I also see some of the foliage seems to be yellowing and browning. Any advice going forward?

A: What you are seeing happening to the potato blossoms is natural blossom drop. Sometimes potatoes set fruit (which look like small green balls), but they often don’t. There is no need to spray any insecticide. The blossom drop will not affect your potato crop.

As for the leaf symptoms, this looks like decay that can occur when leaf tissue is in contact with the ground. If that’s the case, simply prune this leaflet off. If you are seeing many yellowing symptoms on other parts of the plant that aren’t touching the ground, please send some additional photos of the whole plant, so we can see its position in the landscape and the condition of the entire plant. You can also consider sending a sample to the UMaine Extension Plant Disease Diagnostic Lab for identification.

split radishQ: What is doing this to our radishes? It has happened to only a few, not all of them.

A: It looks like your radishes have naturally split, which is more common this time of the year as the Spring radish season comes to an end. Radishes will split when they are getting too old; most varieties of radishes are ready to harvest between 21-28 days after planting and prefer cooler temperatures. Radishes will also split due to uneven watering or when there is heavy rainfall after a period of dryness. It’s not uncommon for splitting to happen to only a few radishes at a time.

Q: We have a ton of pine needles that just fell. Can we cover our potatoes with them? Can we use them to mulch anything else?

A: Yes, you can use pine needles as a mulch for your garden, including your potatoes and other annuals you may be growing. Pine needles can also be used for perennial gardens.

Damaged Oak treeQ: Wondering what might be doing this? It started with one of our oak trees last month and is now showing up on other trees, also in the flower and vegetable gardens on the hostas, rhubarb, and kale. Several little holes in the leaves. We have been looking daily for any sign of caterpillars or beetle-type bugs, but nothing yet. The trees are about 16 to 24 feet tall. I don’t think the problem is caterpillars. They fly and it’s always at dusk. We don’t see any caterpillars or nests or webs. Two of the oak trees are pin oak, plus we have a couple of maple.

A: Thank you for sending the photo. It’s very helpful. I believe you are seeing European Chafer Adult Beetles flying around at dusk, they usually fly from 8:30 pm to 11:30 pm around large treetops.

As for the damage you are seeing on your oaks, it looks like it’s being caused by Oak Shothole Leafminer, which is actually a native to Maine. Most of the damage is caused by the adult female fly feeding on the leaves. I wouldn’t worry too much about this Leafminer because they are not considered a significant pest of oaks and your trees should be able to bounce back just fine.

For more information about Oak Shothole Leafminer, check out this article by UMass Extension.

Black SwallowwortQ: I have an invasive weed that looks like wild morning glory but does not flower. It produces pea pods in the fall. I have included a picture. Any advice?

A: Thank you for sending the photo. It appears you have Black Swallowwort (Cynanchum louiseae), which is listed as an invasive species in Maine. Those purple parts on the plant are the flowers. I would do whatever you can to control and eradicate this invasive plant.

Here is a link to more information this plant and effective control measures you can use: Bulletin #2523, Black Swallowwort.

Q: Is this poison ivy?

Asiatic Bittersweet
Asiatic Bittersweet

A: Thank you for the photo! This is not poison ivy, but it is Asiatic Bittersweet (Celastrus orbiculatus), which is an invasive species in Maine. If you found this plant on your property, I would recommend doing your best to eradicate it. For more information and recommendations for control measures to use, check out this Bulletin #2506, Asiatic Bittersweet.

Poison Ivy can be identified by each leaf containing three leaflets, these leaflets are usually alternate along the main vein. For more information and photos, check out the State of Maine’s webpage on Poison Ivy.

Q: I just discovered a bittersweet nightshade vine (not Asiatic bittersweet) growing on my back fence. I don’t have children, there are no children in my neighborhood, and I don’t have outdoor pets. Should I dig it up and get rid of it anyway? Aside from the toxicity will it become an invasive problem?

A: Thank you for providing the photo. Bittersweet nightshade (Solanum dulcamara) is not considered an invasive species in Maine, so there is no need to dig it up unless it becomes a weed in your garden or lawn.

Apple Cider Hawthorn RustQ: We have a fruit tree by our front window. The berries are red. We noticed that some of them are swollen and fuzzy.

A: This is Apple-Cedar-Hawthorn Rust.

Q: We have an overgrown grapevine in our yard. I would like to cut it back so we could put it on a trellis, as it is climbing other trees and killing them. How can we go about cutting it back and getting it on a trellis?

Edelweiss grapes on the vine
Photo by David Handley.

A: Grapes should be pruned while the canes are fully dormant, usually March is a good time for pruning. It is best to prune overgrown grapes in stages with the goal of re-establishing a single trunk and selecting canes that will be well-placed for your trellis system.

  1. Begin by selecting a new trunk from the base of your grapevine. Cut the new trunk back to the desired height and secure this trunk to your trellis system.
  2. Choose two young canes on each side of the vine and tie them to the trellis. Young canes will be about 3/8” in diameter and a chocolate brown color.
  3. Remove any old wood (2+ years), weak, injured, or diseased canes. You’ll be removing a lot of wood if you have a neglected vine.
  4. As your vine grows during the season, secure the new growth to the trellis system. Don’t be afraid to prune and train the vine as needed.

For more information about growing grapes, check out Growing Grapes in Maine by David Handley, Vegetable & Small Fruit Specialist, UMaine Cooperative Extension.

Q: We planted red clover as a cover crop this spring. It is growing well, but we are unsure of the next step in the management process. It’s currently about 8 inches and has not come into flower yet. Should this be mowed prior to turning under? What is the best time to turn it under? Is that space available to plant back to our vegetable garden next summer?

A: Red clover is a biennial here in Maine and requires very little management before turning under. If you seeded the red clover in the late Spring, then it’ll be ready to incorporate in the Spring of next year. You could mow the clover before turning it under, but it’s not absolutely necessary. Yes, you should be able to plant vegetables in this area of your garden next summer.

Q: I have moved to a new home and discovered that I have a male/female kiwi vine growing rapidly in our yard. It is a Hardy Northern Kiwi plant. Am not sure how old it is? When will it produce? How can I enhance this vine?

A: Hardy Kiwi will begin producing fruit at 5 years old. Although Hardy Kiwi is hardy to Zone 4, it still requires at least 150 days of frost-free temperatures to produce a ripe fruit, which means this fruit needs to be harvested before the fruit has ripened on the vine. Hardy Kiwi will ripen in the refrigerator, but it doesn’t have a long shelf life, so enjoy it sooner rather than later.

Hardy Kiwi should be pruned during the dormant season, ideally in late March or early April to encourage quality fruit. It should also be pruned throughout the growing season by cutting back the flower shoots to 4 to 6 leaves beyond the last flower.

For more information on Hardy Kiwi, check out Hardy Kiwi in the Home Fruit Planting from Penn State Extension or Hardy Kiwifruit from Cornell University.

holly bush with brown leavesQ: My holly bush had a rough winter and many of the leaves have turned brown. What can I do to help it recover?

A: This has been a very common question this year. Many broadleaf evergreens were hit hard by the wind last winter. Thankfully, they should recover just fine. There’s no need to do anything special to help them along, just have patience.


Q: I planted early, mid-, and late-season varieties of potatoes at my common share community garden in Portland. They’re in different rows. The mid-season potatoes are much bigger and flowering profusely. The late-season varieties have fewer flowers on them and the early season potatoes have very few flowers. Should I expect them to be harvested differently than I expected:

    • Early potatoes: 55-70 days, July 3 – July 17, is 10 weeks mid-July
    • Mid-season potatoes: 70-90 days, July 17- Aug 7, early Aug
    • Late season: 90-110 days, Aug 7- Aug 28, late Aug/early Sept

A: The amount of flowering has little to do with the size and maturity of potatoes. Some varieties don’t make many flowers, while others will produce many. There’s also great variation in the stature of different potato cultivars. I would expect that the late-season varieties will stay green after the others have started to die off. Prepare to harvest when the tops turn brown. Leave them in the ground about 2-3 weeks after they die back to set skins for better storage.

Q: Is it possible to plant green beans now? Should they be started in small containers and brought in at night to give a head start/more warmth?

A: Now is a great time to plant a crop of beans. Simply sow the seeds directly into the garden and give them 1 inch of water a week. In central Maine, we have approximately 84 days before the first frost. Be sure to choose a variety that will ripen in the time you have left. Most traditional bean varieties are between 50 and 60 days to harvest.

Q: We are in East Boothbay. My husband wants to release Trichogramma wasps to combat brown tailed moths. Comments?

A: After consulting with the Maine Forest Service, the release of Trichogramma will most likely do nothing to control browntail moth. Trichogramma are not on the unrestricted list for import for IFW, so a permit would be needed.

Pine tree with orange pine neeedlesQ: We planted five white pines in our yard five years ago. One turned orange and we cut it down. The one next to it has turned orange, so we will probably have to take it out, too. Is there anything we can do to save the other three? Please see photo.

A: I have spoken with our Plant Pathologist. She has informed me it could be one of two needle diseases they’ve been seeing, but she would need a declining green tissue sample to determine which one.

Please submit a branch sample to our lab in Orono, using these submission guidelines. There is no fee to submit a sample; you simply need to pay for the shipping cost. Here is the link for the Plant Disease Diagnostic Submission Form (PDF).

rhubarb growing in the gardenQ: What is the best way to harvest rhubarb? I have always cut it with a knife. I have recently heard that it is better to pull a leaf from the ground.

A: You can harvest rhubarb either by cutting it right above the base or by pulling and twisting the stalk until it snaps off. Either option works just fine.

Q: I enjoy the fragrance of stock, but the flowers go to seed so fast and the fragrance is lost in a couple of days after I cut some and bring them into the house. I use a raised garden in Gardiner, Maine. Is there any trick to extend the life of stock’s fragrance or are there any fragrant flowers with a longer “shelf life” when blooming?

A: Unfortunately, stock doesn’t have a very long shelf life, but one thing you could try before putting the flowers in water is giving the stem one 1/2-inch vertical cut up the center of the stem. This cut should help the flower take up water more quickly, which will improve its shelf life and likely help prolong its fragrance.

I would also recommend planting Dianthus, Snapdragons, and Sweet Pea, if you prefer fragrant cut flowers.

Q: How do we keep the critters and birds from eating all the cherries on our tree without doing something toxic?

A: The best way to keep critters and birds from eating all of your cherries is to use bird netting. It can be a little time consuming to set up and break down, but it’ll ensure you’ll be able to enjoy some of those cherries.

Q: I have just planted some Ranunculus in a container. Do these have to be dug up for the winter? I live in Winterport, Maine. I am not sure what zone I am in.

A: You are in zone 5B. Ranunculus is treated as an annual in Maine, so it would be dug in the fall and planted in spring. Lift the corm when the foliage yellows and begins to dry out. Allow the corm to dry off for several days before storing in a crate packed with peat moss in a cool, dry location until it’s time to replant next year.

Q: Can I use Hemlock shredded mulch on my perennial garden on Swan’s Island? Is it too acidic, or more acidic than a cedar mulch?

A: Shredded hemlock mulch is absolutely fine to use in your perennial gardens and will not result in a significant alteration of your soil pH.

Q: We have a nice wild cherry tree at our lot in Denmark. I was curious if we pruned and fed it would it produce larger cherries? There is another tree nearby for cross-pollination.

A: Fruit size is more closely associated with the genetics of the plant and seasonal moisture conditions than fertility and pruning. Pruning the wild cherry is certainly not a bad idea, but won’t necessarily lead to larger fruit. It’s best to take care of that task in late winter/early spring before the buds begin to swell. Fertilizing native plants in their native soils is generally not necessary. You can always do a soil test to make sure there aren’t any nutrient limitations or pH adjustments that might be needed, but I wouldn’t add anything without that information first.

Q: What are some small compact flowering shrubs that grow no taller than two feet and like full sun about 3/4 of the day? I live in the Westbrook, Maine area. My soil is mostly clay, but I have amended all my garden beds with compost, peat moss, and bags of garden soil.

A: There are a lot of great options for your site. Some that quickly come to mind are:

  • Clethera alnifolia ‘Crystalina’ or ‘Sugartina’
  • Cotoneaster apiculatus
  • Deutzia gracilis (there are a few different low-growing varieties)
  • Fothergilla gardenii
  • Hydrangea paniculata (there are several low-growing options)
  • Iberis sempervivans
  • Spirea (numerous low-growing options)
  • Stephanandra incisa ‘Crispa’
  • Rhododendron ‘Purple Gem’

Q: I have Bishops Weed and Snow on the Mountain. Is there any hope of getting rid of it?

A: There’s hope, but it’s important to be persistent and patient. It’s best to start by trying to remove as much of the root system as possible using a garden fork to loosen the soil deeply before weeding. Grab every single piece of root; each one has the potential to develop into a new plant. As you can imagine, getting every little bit is impossible. Therefore, the next step is to place a physical barrier, such as cardboard topped with bark mulch or wood chips, for a season before installing new plants in that area. If you’re in a hurry to replant, monitor the new planting on a very frequent basis for any strays that pop up. It’s reasonable to expect that strays will pop up for many years after initial eradication efforts. Be sure to your best to not let them get a foothold again!

Straw washing up on shoreQ: We live on a small cove on the Sheepscot River. There is a lot of what looks like straw that has washed up on shore, particularly after windy days. Can I clear this off? It seems to be killing the natural grass-like plants below it. Someone has told me that it is a good fertilizer, which can be used around other garden plants. Is this true?

A: I reached out to our friends at Maine Sea Grant and they suspect that it’s last year’s shoots of Phragmites, an invasive plant that’s spread over much of Maine and the northeast. It’s possible that the native vegetation will grow up through it eventually, but it doesn’t hurt to pull it away and use it as a mulch in your garden. I doubt that it will provide a significant amount of fertility, but it can serve as a good weed barrier and help keep moisture in the soil.

Q: My daughter’s garden in Portland is invaded with Artemesia vulgaris. I have tried to dig it up twice, but it has come back with a vengeance. How can I permanently remove it?

A: A. vulgaris is a very challenging invasive perennial to manage. In most home landscape situations, the best approach is to mow the patch very closely to the ground and cover with cardboard topped with some type of heavier mulch (bark mulch or wood chips both work well). You’ll want to wait at least a year or two before removing that barrier and planting something else in that area. If there are any perennials growing within that patch that you’d like to rescue, dig them up, carefully weed out any A. vulgaris roots, and temporarily transplant them into pots. I recommend potting them so you can monitor them for any A. vulgaris stowaways. If you’re looking for chemical control options, I’d like to talk with you on the phone first to gather more site details such as the size of the patch, proximity to surface water, other nearby plants and whether it’s near a well.

Plum tree, with dries leaves and new leavesQ: I have two plum trees that have bloomed beautifully since I planted them about eight or nine years ago. In the last few years, I’ve gotten great, small plums. This year the blossoms dried up before opening and there are no leaves. Any ideas?

A: I noticed some new growth in the photo. Therefore, I’d give it some time to hopefully recover. I suspect that you’re dealing with some winter damage as well as new growth that was hit by the cold and wet weather we had this spring.

I recommend sending us a sample. Here’s information on how to submit a plant sample to our Diagnostic Lab.

Q: I’ve had two dogwoods for 13 years with never a problem. This year, they were loaded with buds but did not bloom. Are they possibly gone as a result of the Maine winter? Should I have them removed, or give them more time?

A: After talking with the client, we determined that the lack of growth is very likely due to winter injury. Many other well-established (previously healthy) woody plants in her windy site are also suddenly having a lot of dieback. The stems are green when they’re gently scratched, so there’s likely still plenty of life in the tissue to rebound. With the slow spring we’ve been having, it’s very understandable that the new growth hasn’t emerged just yet. A lot can happen when the weather warms in the coming weeks. She’s going to take the wait and see approach.

Q: Do the following need to be cut back in the fall? Also, when is the best time to trim and shape Arborvitae used for a screen?

  • Rudbeckia
  • Shasta Daisy
  • Phlox (full-sized)
  • Bee Balm
  • Columbine
  • Hydrangea

A: You can cut back any herbaceous plant in the fall, which would be Rudbeckia, Shasta Daisy, Phlox, Bee Balm, and Columbine on your list. Hydrangea is a woody plant, so it shouldn’t be cut back in the fall, but you can prune it as needed.

The best time to trim and shape Arborvitae is in the early spring when buds are swelling, but before they begin to elongate.

Q: I live in Bath, where we’ve had a long, cool/cold spring with plenty of moisture. I think one of my peonies may have Phytophthora Blight. Is this a known problem in Maine?

A: It is very unlikely Phytophthora Blight is the issue. Phytophthora Blight is generally an issue on woody plants with the exception of potatoes. There’s a good chance it could be Botrytis, which has been identified on similar plants this Spring throughout the state. The symptoms of Botrytis are dead or dying flower parts, stems, and/or leaves or the appearance of gray mold.

If you’d like to confirm Botrytis is the issue, you can send in a plant sample to our lab in Orono. You will also find instructions and the submission form for plant samples. It is best to send your sample early in the week (Monday or Tuesday) so that the lab receives the sample as soon as possible.

We can sometimes identify the problem via photos, so please feel free to email me a few photos of your peony and we’ll see if we can identify the issue.

Q: Can I transplant Lunaria plants from Connecticut to Boothbay Harbor successfully? Will it thrive?

A: What species of Lunaria are you trying to relocate? If it’s Lunaria annua, it will be hardy enough to overwinter in Boothbay Harbor and re-seed reliably. Since it’s a biennial, L. annua would be best to propagate from seed rather than transporting the actual parent plant. Plus, it’s best to avoid transporting home-grown field-dug plants as the soil surrounding the roots can possibly carry unwanted species into our state.

apple tree damaged by sapsuckersQ: What is doing this to our apple tree?

A: It looks like sapsucker damage. Sapsuckers and other woodpeckers can be tough to discourage once they get established in a certain area. Hardware cloth wrapped around damaged areas can help protect those spots from further damage, but won’t keep the birds from choosing another spot on the same tree to feed. Using protective measures along with scare tactics (hanging pie pans, reflective strips, fake owls, etc.) may enough deter the birds. See the fact sheet Woodpeckers and Sapsuckers from the University of Maryland Extension for more information.

Q: I just built some raised beds, but am not sure what type of soil to fill them with. I was thinking I should use a mixture of loam and compost. If that is a good choice, could you tell me what ratio of compost to loam I should use? If it’s not a good choice, could you suggest a better one? I will be hopefully be growing vegetables in the beds (tomatoes, kale, zucchini, cucumber, Brussels sprouts).

A: You are right, a mixture of loam and compost works well for raised bed gardens. We like to see at least 25% by volume as compost and 75% loam. If you mix it in a wheelbarrow, then you could add one 5-gallon bucket of compost to three 5-gallon buckets of loam. Our fact sheet, Gardening in Small Spaces, has some more information on raised bed gardens.

HorsetailQ: I began preparing a 50 x 100 foot area near our house three years ago and put in six large raised beds for growing vegetables for our family. When we prepared the area, we tilled it with a tractor to help level it and take out some of the brush and roots that were there. I’m afraid in doing so that we spread what may have been a small patch of horsetail into a much larger area. Since then it has grown up through the 2 feet of new soil in the raised beds and is peaking out of any area we have tried to cover with tarps or heavy landscape fabric. I’m afraid it is going to take over the whole garden we have been working so hard to establish. What is the best way to eradicate it? I don’t think digging it up is an option. Should we spray? Or till and tarp? So far, covering it with heavy-duty tarps (not silage), it continues to grow. It is just so disheartening.

A: Horsetail is an ancient plant that can be hard to control. Our cranberry site has a page about controlling horsetail in cranberries that suggests lowering the pH and improving the drainage. If you haven’t already done so, you should do a soil test of your raised bed soils and adjust as needed. You could also do a separate soil test for the walkways and if the pH is near 6.0, you may want to think about using sulfur to lower the pH just in the walkways between the raised beds.

The University of Illinois Extension has a website on the control of horsetail. It is interesting that they suggest a slightly higher pH may help with control. They also suggest improved drainage and to reduce irrigation. They have a number of herbicide suggestions that can be tried too. Whenever using a pesticide be sure to read and follow label directions.

Q: For the last two years we have had trouble with Black Spot fungus on our tomatoes. How do we remedy this problem? We live in Brunswick, growing in organically enriched raised beds.

A: I suspect your tomatoes have Septoria Leaf Spot. We have a factsheet, Septoria Leaf Spot of Tomato, on the disease with suggested management actions you can take.

  • Be sure the tomatoes are spaced apart so there is good air movement. Staking or trellising can help.
  • Hand pick the lower leaves as they start to show symptoms.
  • Stay out of the area when leaves are wet.
  • Water early in the day so leaves won’t be wet in the evening.
  • Be sure plants get adequate nutrition.

You can use organic fungicides to prevent infection. Start with a copper-based spray as soon as possible and repeat every 7 to 14 days. A list of fungicides is included in the fact sheet.

Of course, be sure to read and follow pesticide label directions.

You may want to send a picture of the leaves or send the leaves themselves into our Plant Disease Lab, to confirm Septoria Leaf Spot. Other tomato diseases such as early or late blight have disease-resistant varieties that can be used in the garden.

Q: I have a large vegetable garden that I have been carefully tending for 30 years. I regularly add compost that my husband lovingly makes. In a few small areas, there are liverworts and moss growing. I read online that this can be an issue of soil compaction and poor drainage, and that I should add compost. Is there likely to be a pH issue also? Do liverworts thrive on acid soils or basic soils?

A: You are right that mosses and liverworts prefer compacted, poorly drained soils. They also prefer shady areas.

Mosses do prefer acid soils, but before you start adding lime to sweeten the soil, you should do a soil test. Here is our information on soil testing.

In 2017 we had a similar question about liverworts. Here is the response we gave then.

What you have growing in your garden is a type of liverwort, a prehistoric plant that typically grows in a shady, moist environment. Liverwort is sometimes a serious problem for large-scale growers of container plants and greenhouse growers. Research showed that drying the surface, then mulching, limited it. Nowadays, that’s the reason many pots are mulched with gravel or filbert shells.

In your garden:

  • As much as possible, allow the soil surface to dry. Perhaps water less often, but longer for each session so that your desirable plants continue to thrive.
  • Use fertilizer judiciously, reducing the amount you use and, when you do use it, place it around individual plants that need it, then lightly scratch it into the soil.
  • Because liverwort has shallow roots, it’s easily scraped off the soil surface; then add an inch or two depth of mulch of your choice.
  • Repeat the above as needed, while realizing you must be persistent. It’s important to know that most herbicides won’t work. The reason: liverwort isn’t a vascular “plant.” Then, too, no home-use products are labeled for liverwort.

Liverwort (PDF) from the Oregon State University Department of Horticulture was written for commercial operations but is helpful information. For more general information, see liverworts, which are actually quite interesting plants!

Unhealthy leaves on peach treeQ: Our new peach tree has a brown crinkly situation throughout on its leaves. Also, one of our lupines looks wilted and has odd misshapen leaves. Any advice?

A: It looks like your peach has Peach Leaf Curl. Our Growing Fruit Trees in Maine website says the following:

Peach leaf curl causes leaves to become thickened and puckered. In some cases, the leaves develop an orange or red color. Infection occurs just as buds begin to swell in spring, but symptoms do not appear until a month after bloom. Wet weather favors infection. The varieties Avalon Pride, Betty, Elberta, Frost, Harken, and Redhaven have some resistance.

A single fungicide spray before bud burst in spring will give nearly complete control. Effective fungicides include copper sulfate, Bordeaux mixture and chlorothalanil. When a high degree of control is desired, apply one of these before buds swell. Once infection occurs, this disease cannot be controlled.

Wilted lupineI’m not sure what is happening to your lupines. Have you sprayed anything near them? Used any lawn clippings that had been treated with a herbicide? Is there any feeding damage to the stem near the ground? Did you have a frost that may have affected part of the plant that was least protected by the house or other vegetation?

Sorry, I only have questions, not answers for your Lupine question.

Ostrich fern fiddleheads
Ostrich fern fiddleheads. Photo by David Fuller.

Q: Where can I find fiddlehead plants?

A: Fiddleheads or Ostrich ferns can be hard to grow. You need to have the right location. Ostrich ferns grow primarily along stream and river floodplains in part shade, under the canopy of trees such as red and silver maples and brown ash. Our bulletin, Ostrich Fern Fiddleheads includes information on ostrich fern biology, identification, season, sustainable harvesting guidelines, safe handling tips, and marketing considerations.

We do have a fact sheet, Native Plants: A Maine Source List, that a number of nurseries have indicated they carry native ferns. They may or may not be Ostrich or Fiddlehead ferns, but this is the best list we have for potential sources of plants or spores.

Q: I have been hesitant to plant my tomato seedlings outside because the weather has been so cool. Do you think it is safe to plant them outside? I live in Brunswick.

A: May 30 in southern, coastal Maine, you should be fine planting your tomato seedlings in your vegetable garden. I still watch the evening weather report just to be sure a frost isn’t predicted. If there is a frost you can cover your plants to protect them.

We do have a planting chart for central Maine. You can plant a week ahead of these dates. We also have a site that has suggestions for keeping your gardening growing from spring to fall.

Q: How do I get rid of Oriental Bittersweet? After I cut it out, how should I dispose of the cuttings? Do I need to use a herbicide? Is there a safe brand?

A: Oriental Bittersweet is one of Maine’s invasive species. The Maine Department of Agriculture has a website devoted to Oriental & Asian Bittersweet. That includes a lot of links for identification and control.

Cutting before they go to seed is best. If you had a small patch, you could try to dig up the roots too.

Once the stems are cut, you should bag the tops and take them to the landfill as trash.

Immediately after cutting you could do a stem treatment with either triclopyr or glyphosate herbicides by a cut stem application. You can use a foam paintbrush to brush the herbicide on the cut stems. See the label directions for mixing with water. Read and follow label directions. You can do the cut stem treatment anytime the plants are actively growing but before cold weather.

potatoes; photo by Edwin RemsbergQ: I have some seed potatoes from my garden last season. The eyes have grown to skinny stalks, four to six inches long. Should I clip them back to an inch or so before planting?

A: Hopefully you have certified seed potato and not potatoes that you harvested last fall. Usually, potatoes don’t last a year and a half. That being said, the four to six-inch long stalks should be planted with the tuber. Just lay them down in the row and cover with soil. Potatoes stems will develop “adventitious” roots when in contact with the soil. I would not plan on a huge harvest and suggest purchasing some certified seed to round out your garden. Our fact sheet, Growing Potatoes in the Home Garden, has a list of suggested varieties.

Q: We live in Kennebunkport, Maine. Can we plant our vegetables outside at this time, Memorial Day?

A: May 27, in southern, coastal Maine, you should be fine planting your vegetable garden. I still watch the evening weather report just to be sure a frost isn’t predicted. If there is a frost you can cover your plants to protect them.

We do have a planting chart for central Maine. You can plant a week ahead of these dates. We also have a site that has suggestions for keeping your gardening growing from spring to fall.

Q: When can I move my vegetables outside in Maine?

A: It depends where you live and what you are planning to plant. Cold tolerant crops (cabbage, broccoli, cauliflower, etc.) can be put in as soon as the garden soils are prepared. Cold sensitive crops (peppers, tomatoes, cucumbers, etc.) can be planted in southern Maine or along the coast on May 25th. Central Maine gardeners should wait another week to June 1st. and Aroostook gardeners may want to wait a little longer. You should still check the weather in the evening to be sure no frost is expected. If frost is expected, cover cold-sensitive crops. We have a website with a planting chart that can help determine when to plant in the garden.

Soils should be 55 degrees, 3 inches down before crops can be seeded. If you have a well-drained garden you may have warm enough soils. Seeds treated with a fungicide can tolerate cooler soils.

We have another interesting website that includes a chart so you can have vegetables coming all summer long with spring to fall plantings.

Unhealthy Raspberry CaneQ: Last year’s raspberry plants (purchased in 2016) grew well and then wilted and died in one area of one row. This year in the same row but not the same area, canes were growing well with lots of leaves and then yesterday I found some canes had rotted off at the base. What would be the treatment for this condition and treatment for the currently healthy plants? The ground is sloping and not heavy clay.

A: It is hard to tell from the picture, but if there is a small hole or black spot in the middle of the cane then you could have cane borers. They will affect the new growth and will cause a classic shepherds hook at the top of the cane where the female laid her egg and girdled the stem. If you see them this year, cut them off just below the two girdling rings, and throw away, do not compost. UNH has a nice factsheet on Raspberry Cane Borer (pdf).

If you don’t see any hole in the center of the cane, then you may have root rot. It is usually a problem in poorly drained soils. To be sure, you can dig up the plant that isn’t doing well. If it only has a few roots and if you strip the bark from the root and it looks reddish-brown underneath, then you may have root rot. You can send a sample to our plant pathologist to be sure. Go to UMaine Extension Insect Pests, Ticks and Plant Diseases to print a submission form. Complete the form and mail it along with the plant sample. Also, see Penn State’s factsheet on Phytophthora Root Rot.

Q: We have a very productive raised-bed garden outside of our office. This winter we had rats (woodrats, we were told) in our building. They were exterminated. Now there is concern that we should not grow vegetables because rats likely live nearby. Is there any reason to not have a garden because rats may live nearby?

A: If there is no evidence of rats digging in your garden, I would think you should be fine. We do have guidelines for folks planning to use fresh manure in their garden to wait to harvest 90 days for vegetable harvested from the aerial parts of the plant (like peppers) and 120 days for root vegetables (like radishes).

unhealthy cotoneasterQ: My cotoneaster starts out fine in the spring but halfway through the last two summers they succumb to some sort of blight or fungus. The leaves begin to turn brown, dry out, and crumble. Is there anything I can spray on them? The plants cover a large area of my garden and are about 16 years old. Some branches are starting to die.

A: Cotoneaster can be susceptible to Fireblight, winter injury, or drought. I can’t tell from your picture what may be happening with your plants. To rule out Fireblight, you could send a sample that includes twigs with both diseased and healthy leaves to our plant disease diagnostic lab. The UMaine Extension: Insect Pests, Ticks and Plant Diseases web page will tell you how to collect, package, and send your sample along with the submission form to let them know more about the plant. They should be able to give you an idea of what is wrong with your plants.

Q: I live in the town of Penobscot in Hancock County. Quite a few years ago, I planted a peach tree and the last few years, it’s flowered (like right now), started growing many little peaches, and then, the peaches were covered in some bug/beetles that killed all of the peaches. It’s so discouraging. What are these bugs and what can I do to save my peaches? I haven’t even gotten one!

A: You are lucky to be in an area of Maine where peach trees can survive the winter. Have you been able to take any pictures of the bugs that are attaching to the baby peaches? Are you using any insecticide to manage insect pests on the peaches? Our website “Growing Peaches in Maine” provides some cultural suggestions to follow. This year, if the bugs attach, please try to take a picture or collect a few and get them to your local UMaine Extension Hancock County office.

Q: Does your organization sell saplings? In particular, I’m looking for six red maples. If you do not, could you recommend someone who does?

A: Many county Soil and Water Conservation Districts have plant sales that include trees and shrubs. They are usually by pre-order that occurs earlier in the year.

The Maine Department of Agriculture, Conservation and Forestry maintain a list of licensed nurseries. You can search for a location to see if there is someone near you.

apples on treeQ: We have a yellow transparent apple tree that produces apples that are attacked by birds, hornets, caterpillars, and ants, causing the fruit to get circled, eaten from within, and otherwise destroyed. Is there any product or practice that can help us avoid the problems?

A: As you have seen, apple trees can attract a variety of pests. The bird damage to the apples can attract hornets and ants to feed on the inside of the apples. There are caterpillars that feed on the fruit and also some that feed on leaves. Our web page Growing Fruit Trees in Maine: Insect Pests includes a number of organic and non-organic pesticides that can control insects that feed on the fruit or leaves.

Some of the leaf eater insects may also build a web or nest in the tree, like Eastern Tent Caterpillars. Our factsheet on this pest recommends removing the nest when you first see it to control them.

Applying netting to a tree can prevent bird damage, but any fruit next to the netting may be damaged. Some home gardeners build a frame around their tree (if it is a dwarf or semi-dwarf tree) and suspend nylon bird netting from the frame. Some home gardeners use scare devices like streamers, plastic owls, aluminum pie plates hung on the tree or balloons with large “eyes” on them.

peach shootQ: What should I spray my peach tree with?

A: This time of year we are thinking about controlling Brown Rot on the blossoms and twigs of peaches and other stone fruit. First, be sure you remove any mummified fruit still on the tree or on the ground. These are a source of infection.

There are a number of fungicides that can be used by the home gardener and our factsheet Brown Rot of Stone Fruit lists both organic and non-organic fungicides. Be sure to read and follow label directions.

Timing is important. Fungicides should be sprayed just as the blossoms start to open and again when most blossoms are open, to protect for blossom and twig blight caused by brown rot.

Pruning will help increase air movement in the trees and is another cultural control.

raised bed gardenQ: My husband and I raise vegetables in the woods of western Maine using raised beds. For the past few years, we have been plagued with blight, which impacts our tomatoes and other nightshade plants. In the Fall, we clean up by placing all plants, stems, etc. in black plastic bags, which are placed in the trash. Yet, we continue to have blight issues. This year we have taken down the retaining walls for these raised beds, but have left the soil. I think we should scrape off the soil and remove it to the woods. My husband says that removing the soil and replacing it with clean soil from away will not work since the spores probably continue in the area. So, we are wondering what you might suggest at this point. We plan to leave our vegetable garden fallow this year and are willing to learn if there is anything we can do to remediate (eradicate) this problem. We use compost that we make from kitchen scraps, debris from flower gardens, and leaves. Could this also be an unwitting source of our problem?

A: It sounds like you have been doing a number of things to reduce the incidence of blight. Have you had the disease diagnosed to see if it is late blight or early blight?

You mentioned you are in the woods. Does your garden get at least 6 hours of unfiltered light?
Do you grow your tomatoes on trellis or poles to get them up away from the ground? When you do this, do you also thin the plants so plenty of air circulates around the leaves?

Are you using any of the disease-resistant varieties of tomato? The New England Vegetable Management Guide lists a number of Early Blight and Late Blight disease-resistant tomato varieties.

We do have a fact sheet on Early Blight of Tomato that has a number of cultural recommendations as well as fungicide options.

Q: What happened to my rhododendrons this winter? The leaves are all brown. Are the plants dead? Diseased?

Rhododendrons in bloomA: The answer to this question comes from Carol Yee, Carol’s Collectibles Nursery:

The wind was the worst in Maine since I’ve been here 10 years. I have never seen such desiccation on so many Rhodies. Ice instead of good snow cover didn’t help. I advise that you don’t panic and wait to see them come along with their new growth. You can clip off the dried leaves at any point and if the stems look dried scrape a tiny bit to see if green shows. If stems are brown cut them also until you come to green. Just in case, dispose of all this somewhere safely away from your plant.

Four years ago, the voles loved the freedom to tunnel under the huge snows of that year. When I uncovered the Rhodies there wasn’t a leaf or bud on any of the hundred or so. No sales that year but every one refoliated by Summer and bloomed the next year!

Keep the faith! I believe they will be okay.

Q: I have a question about trees. Between my house and my neighbor’s commercial building is a space of about 15-20 feet. Both structures are about 150 years old with granite foundations. I planted some trees, Blue spruce and fir, about 16 years ago between the properties. The neighbor is worried about their roots impacting his foundation. How can I find out if that is a risk? The trees are very tall now. There are four of them. No damage seen as yet.

A: Whether a tree will cause damage to foundations depends on the type of tree, growing conditions at the site, and how close to the building foundation. Pine family species (fir, spruce, pine) usually cause the least amount of damage to foundations and sidewalks, but if the distance between your two properties is only 20 feet that means there are only 10 feet between the tree and a foundation. If the roots don’t become a problem, the overhanging branches will be an issue in the future. A factsheet from Michigan State University, Reducing Damage Caused by Tree Roots, suggests some cultural practices of not watering or fertilizing the soil near the foundations to discourage root growth. Eventually, the trees will need to be cut down and replaced since they will outgrow that space.

Q: I planted two three-foot-high Aronias about two weeks ago and now need to move them to another location. If I’m careful to get all of the roots, would that be a problem?

A: That should be fine. If we don’t get rain, be sure to water regularly until they get established.

Q: What “creature” turns my onion sets upside down and puts them in piles?

A: That is an interesting question. You could set out a game camera to try to catch the culprit. Do you leave a small bit of the set sticking up out of the soil after it is planted? Birds might mistake that for a worm and pull it up. I don’t know why they would put them all in one pile.

When you plant them again, be sure to cover the dried leaves of the end of the set with soil.

Q: I have established perennial gardens and the soil is not level in some places (after removing weeds), so I need to add some soil. I have been using Coast of Maine Dark Harbor blend each year. What should I use to add quality soil to areas of my garden? Also, I, unfortunately, have found some horsetail growing in my garden. I have cut it at the base and put in a ziplock bag and then placed some black tarp at the spot held in place with a rock. Will this do it?

horsetail, Equisetum arvense
Horsetail (Equisetum arvense)

A: Coast of Maine Dark Harbor Blend is meant to be a mulch, not a garden soil. If your plants are showing signs of nutrient deficiency, you should look for either a material that has the term “soil” or “growing mix” on the label. You could also add soil nutrients by using compost or garden fertilizer such as 10-10-10.

Regarding the horsetail, if the infestation is small, continue cutting off the tops of the plants as they emerge. If a large infestation and a tarp is used, the tarp needs to be large enough to slow the plant emergence at the edges. Horsetail doesn’t do well in shade so encouraging other plants to grow and shade the soil is an option.

University of Illinois has an interesting factsheet on Field Horsetail: A Unique But Aggressive Plant.

Q: What is the best way to diagnose and then get rid of chinch bugs in a suburban lawn? Are there grasses that are resistant to them? Are there natural predators that can be introduced? Is it necessary to spray? How quickly can they spread to other lawns in the area?

A: We have a factsheet on Chinch Bugs that suggests using a coffee can with both ends cut off and pressed into the soil then filled with water to detect chinch bugs in your lawn. If you have any, they will float to the top. You can bring a sample into your local extension office for identification. Because the adult chinch bugs can fly, it is difficult to keep them out of your lawn. In the fall, sanitation may remove potential over-wintering sites. If you choose to use an insecticide, early June is the time to spray. See the factsheet for suggested insecticides.

A factsheet from Penn State University, Chinch Bugs in Home Lawns, includes some other non-chemical recommendations. They suggest using an endophyte enhanced fescue or ryegrass seed can repel chinch bug. They also suggest that fertilization and irrigation can hide chinch bug infestations. Big-eyed bugs are a primary predator of chinch bugs.

If you are willing to include clover in your lawn seeding mixture, it can fill in the areas where the grass is damaged by chinch bugs.

Q: I forced pots of tulips over the winter, they have bloomed nicely and have been on the deck now for two or three weeks. The foliage is ripening, still green, and I want to use some fertilizer to help the bulbs so that I can plant them in the ground in the fall. What do you recommend?

Secondly: I have vigorously raked the lawn at the edges of the walkway where snowbanks, ice, and salt have badly damaged the grass. Two weeks ago I applied gypsum pellets, which I know will dissolve slowly. I will sow grass seed. What variety do you suggest and how do I prepare the area for maximum success?

tulipsA: Most tulips that have been forced usually will not bloom again when planted outdoors. That said, many gardeners like to try. Fertilizing at this late stage in their growth won’t make a difference. Keep them moist and in full sun until the leaves turn yellow and dry. Once the leaves are dried, remove the bulbs from the soil and keep in a dry location. Replant in the fall.

For reseeding the edges of your lawn by the walkways, remember the seed has to have good contact with the soil, so it will only work where there is bare soil. We have a factsheet on lawn maintenance that includes suggested grass varieties. Since this is like to occur every year, you may want to include annual rye in your grass seed, so it will come up quickly.

To reduce salt damage in the future you could consider Alternative Ice Melters that are outlined in this UCONN factsheet.

Q: Are Forget-Me-Nots considered to be invasive? They are spreading in my garden, but are nice for early spring flowers.

Naturalized forget-me-nots
Naturalized Forget-Me-Nots, Saint Albans, Maine.

A: In other states, Forget-Me-Nots are considered invasive since it is a non-native and spreads readily. But in Maine it is not on our official Maine Invasive Plant List.

There are many types of Forget-Me-Nots:

  • Myosotis sylvatica or Annual Forget-Me-Not is listed as a plant that does well in dry, shady areas on our page Plants for Very Dry Soil Shady Locations.
  • Myosotis scorpioides L. or true Forget-Me-Not is a perennial that is listed as invasive in other states. The USDA Plants website lists its legal status.

For ideas on what to plant, see Gardening to Conserve Maine’s Native Landscape: Plants to Use and Plants to Avoid.

Q: About 3 years ago I planted a bag of daffodil bulbs in two raised gardens approximately 15 feet apart. The first year they blossomed nicely. The second year, there were much fewer flowers in the right-hand garden. This year the right-hand garden did not blossom at all, while the other garden again bloomed satisfactorily. I decided to dig the bulbs up that were not blooming and was quite surprised by what I found. All the bulbs were about the size of green onions and there were at least 50 of them. I’ve always let the foliage die back after blossoming even though I consider it unsightly! The small bulbs look healthy as does the foliage. Do you have any idea what might have happened here?

daffodilsA: I can see why this would bring out the curiosity. If the bulbs aren’t blossoming this spring that means they weren’t able to store enough energy last year. You said you wait till the leaves die back before you cut them off — good job. Also, I assume you planted all bulbs at 3 times the height of the bulb. Smaller bulbs would be shallower and bigger bulbs would be deeper. Planting too shallow or too deep can affect how the daffodils grow. I also assume to fertilized the beds the same amount.

Growing in shady conditions in May and June can reduce blossoms. Also, poor drainage will reduce plant vitality and so reduce blossoms.

The bulbs that didn’t flower this year can be dug, separated, and replanted as long as the location gets plenty of sun and is well-drained.

Q: Winter moths have been unkind to my apple trees. I used nematodes in August for grub control, banded the trees in fall, and cut out the deadwood this spring. I’d like to fertilize them with holes around the drip line and I’m wondering if 4.1.1 is the best choice? Is there a formula that has less nitrogen and more of something more beneficial for their recovery? Not really concerned with fruit harvest and more interested in recovering from the shock of being defoliated.

A: Usually trees can take one year of defoliation with no ill effects. Multiple years of defoliation will set the tree back. You may want to remove the blossoms to reduce the stress on the tree.
A fertilizer with the ration 4-1-1 actually has 4% nitrogen, 1% phosphorous, and 1% potash. Nitrogen stimulates leaf growth, phosphorous stimulates root growth, and potash helps the whole plant. The amount of fertilizer you use is also important. Our website Growing Fruit Trees in Maine has a page on fertilizing fruit trees says that:

The amount of fertilizer to add will also vary with tree age and size. The recommended rate in the first few years after planting is ½ ounce nitrogen per tree. Fertilizer that contains 10% nitrogen (10-10-10) should be applied at a rate of five ounces of fertilizer to get ½ oz. of actual nitrogen. For mature semi-dwarf trees, apply 3 oz. of nitrogen in a three-foot diameter circle around the base of the tree. Fertilizer that contains 10% nitrogen (10-10-10) can be applied at a rate of 30 oz. of fertilizer per tree to get 3 oz. of nitrogen. Apply only 10 oz. of 10-10-10 to dwarf apple trees.

Whether you should drill holes and insert the fertilizer around the drip line, is a matter of how much time and energy you have. The nitrogen component of the fertilizer is water-soluble and will move very quickly through the soil profile without the use of holes. The phosphorous and potash move very slowly and so would help roots access these nutrients quicker if put in holes. According to a UMass Amherst factsheet on Fertilizing Trees and Shrubs, holes should be 8 to 12 inches deep and spaced 2-3 feet apart in concentric rings around the tree, starting a third of the way out and extending 2 to 3 feet beyond the drip line.

Q: I have five 25-lb bags of an organic lawn booster (Organica, 8-1-1, contains Corn Gluten Meal) and two 20-lb (same company-Organica) of a Microbial Soil Conditioner. They have been stored for many years. I’ve learned that the corn gluten meal can enhance weed growth, depending on the time of application. My question is how would you recommend I dispose of these materials? I’d rather not apply them to my lawn.

A: Since your soil amendments are derived from organic sources, some of the nutritional value may be reduced due to long time storage, but would still be able to provide some nutrients to plants. The corn gluten meal will suppress seeds from germinating and can act as a fertilizer to plants (including weeds) that are actively growing.

If they are still dry and flowable and you don’t want to use them on your lawn or garden, you could give them away to a community garden or garden club in your area. If you need help finding them, you could contact your town or city hall.

apple trees in blossom
Lyle E. Littlefield Ornamentals Trial Garden, located at the University of Maine.

Q: I have seven old apple trees. I have never pruned them, they are too tall. I have every year given them a basic fertilizer, and mulched with mown leaves. The apples are small and sour and the trees have some dead branches that need removal. I would like to get someone to prune, fertilize, and look after them this year for me. I wondered if either a class learning tree care would want to help with this, or if you knew someone I could hire for this?

A: Pruning an old apple tree can improve the size of the fruit, but the variety impacts the flavor more. If the fruit tastes sour and they are ripe and that is a flavor you desire, then I would encourage you to prune and manage the trees. The State of Maine maintains a list of licensed arborists that you can search by town.

But if you are looking for a sweeter apple, you may want to consider planting an improved variety. Our webpage Growing Fruit Trees in Maine has some suggested varieties that are disease resistant.

Q: My question is about the safety of home gardening with yards treated with pesticides for ticks and mosquitoes. We currently live in a Hampden neighborhood on a 1.5-acre plot. The majority of our neighbors have their yards treated for ticks and mosquitoes. We have had the exterior perimeter of our house treated for pests by a commercial pest company and my husband has treated the perimeter of our yard with an at-home insecticide for ticks. I’m a mom to an almost two-year-old and I try to be conscientious by buying mostly organic produce and from our farmer’s market. I am hoping to do a couple of small raised garden beds with my son, but I’ve been hesitant about the likelihood of contamination from pesticides from possibly our neighbors’ yards or our perimeter treatment and the safety of that.

Woman sprays insect repellent into her handA: Thank you for your questions. We are all concerned about being bitten by a tick and it sounds like you and your neighbors are being proactive about keeping ticks at bay. We do have a Tick Lab that has a web page with a lot of information, including a page on Landscape Management for Ticks.

It sounds like you have only treated the perimeter of your property with pesticides. We use a set-back recommendation of 25 feet from a well when spraying a pesticide, so if your garden spot is at least 25 feet away from where they sprayed, you should be fine.

You still should use something to deter ticks when you are outside (Personal Protection) and also be diligent about checking for ticks when you come in.

Q: I need to transplant some very well established high bush blueberries to a new home. What is the best way to do this? Should I remove buds before transfer, how much of the roots do I need, and when is the best time of year to transfer? Anything you can tell me to keep the bushes alive would be so helpful.

highbush blueberriesA: This is a good time of year to be planting shrubs, but digging up a large well established high bush blueberry plant will be very stressful on the plant. First, you should do a heavy pruning of the branches leaving only 5 to 6 of the healthiest branches. The larger the root ball you can dig the better, but you will need to be able to move it out of the hole. Pruning the top and removing fruit buds will try to balance the amount of roots that will be pruned in the process of digging them up.

We have a factsheet on selection, planting, and care of trees and shrubs in the Maine landscape that gives information about transplanting wild plants that may give you some ideas.

Once transplanted, be vigilant about watering.

If you have some plant mortality and want to replace with new plants, here is our factsheet on Growing Highbush Blueberries.

Q: My garden beds and compost piles have been taken over by the Asian snake or jumping worm. Has any progress been made in researching how to control these (I’ve read what I can find on the internet)? Is UMaine doing any research or tracking their progress in the state? I’m in southern York County and am concerned about how fast they spread and the damage they will do to my garden as well as the surrounding forests.

A: That is a tough question. No doubt you have already found the Maine Department of Agriculture, Conservation and Forestry website on Crazy Worms in Maine that includes information on what you can do and how you can report the presence of them in your area. I don’t know of any active research being conducted here in Maine, but the University of Vermont Entomology Research Laboratory has a page devoted to Invasive Worms.

Q: I’m new to starting tomatoes from seed. I’ve planted Early Girl and Jet Star varieties, and they germinated two days ago. They are in our basement over warming lights. Should I bring them to a small backyard greenhouse at this point so that they get enough light during the day now that they’ve poked out from the soil? Do I bring them in at night to make sure they stay warm since they just germinated?

A: Congratulations on starting seedlings! Tomatoes should get 14 to 16 hours of light either from the sun or lights that are 2 to 6 inches away from the leaves. Tomato plants that get chilled (below 55 degrees F) will slow their growth, so it is best to keep them above 65 degrees. For more information, see Bulletin #2752, Starting Seedlings at Home.

Q: We have a very productive raised-bed garden outside of our medical office. This winter we had rats (woods rats, we were told) in our building. They were exterminated. Now there is concern that we should not grow vegetables because rats likely live nearby. Is there any reason to not have a garden because rats may live nearby?

A: If there is no evidence of rats digging in your garden, you should be fine. We do have guidelines for folks planning to use fresh manure in their garden to wait to harvest 90 days for vegetables harvested from the aerial parts of the plant (like peppers) and 120 days for root vegetables (like radishes).

damaged spruce treesQ: I have a row of spruce trees separating my yard from the neighbor’s driveway. One, in particular, is turning brown all the way up against the trunk to about 2/3 of the way down the branches. The very top looks healthy but the bottom is almost all brown. It is also crowded up against the side of another, larger and more healthy-looking tree (though an excavator did damage the bottom of this tree last fall). Help! I use organic practices in my yard.

A: Since the trees seem to be near the road / paved drive, my first thought is salt damage that happened a couple of years ago. Spruce only keep their needles for about three years so the needles deep in the tree turn brown and drop off. Salt damage can cause needles to turn brown sooner and fall off. Another cause might be a needle fungus that was going around a couple of years ago when we had a wet summer. This would also cause the needles to turn brown and drop prematurely. In either case, it looks like you have at least one year of good needle growth. This spring you should have another flush of needles coming in. You can prune off the worst looking branches if the needles don’t come back. Be careful that vehicles aren’t parked continuously near the roots of the trees.

Also see pages 5-6 of this Maine Forest Service Pest Report (PDF). Spruce needlecast diseases are quite common throughout Maine.

Q: We hired a company to build a 10×10 raised flower bed and had them fill it with topsoil. The soil is clay-like, solid, hard clumps. I am certain nothing could grow in it, if I could actually even dig a hole in it! What should we do to amend it?

A: Topsoil can come from any soil type and it sounds like you got topsoil from a site that had a lot of clay. The answer to a multitude of soil issues is to increase organic matter. There are a number of things you can use, but a good choice would be well-rotted compost. Spreading 2 to 3 inches of compost over your bed and working into the top 4 inches of soil will help improve the condition of the soil in your raised bed. Every inch of compost spread on a 100-square-foot area would need 0.3 cubic yards of compost or 8.3 cubic feet of compost.

Our factsheet Home Composting explains how to make your own compost, but it is a long process.

Q: When can I put down Milorgainite on my lawn and plants? Also, when can I put down lime on my lawn?

A: As soon as your lawn is dry enough to walk on, you can apply lime and any other amendments according to your soil test results.

Q: This past weekend I bought a bag of topsoil from a big box store. As I was loading the bag into my vehicle I noticed that the dirt came from Georgia. Is there any harm to using an out of state soil in the yard /landscape around my home?

A: It’s hard to say whether the bagged topsoil you purchased contains anything potentially harmful to your landscape. Any time you bring plants, animals, or soil onto your property, you are introducing new microorganisms and (potentially) insects that weren’t there before. The label on the bag should tell you what is in it, and ideally, provide an analysis of the soil’s nutrient levels. I’d recommend examining the product carefully before adding it to your garden to be sure you don’t see any insects. If you have concerns, contact the manufacturer. In the future, there are many Maine companies producing topsoil and other soil amendments and landscaping products that you may be more comfortable with.

Q: Last year I had what I believe to be wireworms in my potatoes. What is the best way to manage this pest?

Wireworm feeding on a potato. Photo by James Dill.

A: Wireworms are one of the trickiest pests for home gardeners to deal with because they have several alternate hosts, including sod, which is likely what is surrounding your vegetable garden. A Rutgers Cooperative Extension fact sheet, Wireworms (PDF), offers these seven steps to manage wireworms in your garden:

  1. Avoid planting vegetables in infested soils. If wireworms were previously a problem, plant as far away from that area as possible, or rotate to non-host crops.
  2. Avoid planting a garden in soil that was previously sod or out of production. Wireworms build up in sod, and when the sod is replaced by garden crops, the wireworms readily feed on the roots of the new crops.
  3. Plant baits of germinating peas, beans, corn, cull potatoes or stiff dough 2–4 inches deep in holes at 3–10 feet intervals, then cover with boards or tiles. Dig up every 3–5 days and destroy the wireworms that have been attracted to these baits. Another good bait is nearly full-grown carrots, which can be planted every 3 feet apart in the garden. Pull the carrots up after 3–5 days and remove and kill the wireworms from the carrots, then replace the carrot.
  4. Several species of wireworms become abundant in poorly drained soils. The proper drainage of these soils will help reduce populations of these species.
  5. Ornamentals such as asters, phlox, gladioli, and dahlias are attractive to wireworms. Do not keep ornamentals near the vegetable crops to reduce wireworm problems.
  6. Fall plowing and disking will expose wireworms to predators such as birds and other predators.
  7. There are no effective insecticides labeled for use in the home garden for wireworm control. Once damage is detected crop rotation is the best management tool.

Q: I’ve been hearing that it’s best not to rototill a backyard garden plot every year because it destroys the worms and natural underground networks. Others say doing it at the beginning and end of the growing season is fine. I’ve done both ways and wonder what the experts say?

A: The answer is: it depends. In general, the less you till, the better off your soil structure, organic matter, soil microbiota, and air/water infiltration will be. Tilling can increase compaction, bring weed seeds to the surface, and, as you mention, damage beneficial organisms like earthworms and beetles that naturally aerate the soil and cycle nutrients.

Of course, there are sometimes really good reasons to till. If you need to quickly incorporate soil amendments like compost or lime, tilling them in gives those materials more contact with the soil more quickly and allows for faster changes. Also, if you are direct seeding small-seeded crops, a smooth seed bed is often called for.

The best thing for your garden is to get to know your soil with an annual or biannual soil test, keeping records of your planting maps and management activities (like tillage and application of amendments), and observing how these things change over time and in response to those activities. If you do not need to till, great! If you do, just be aware of all of the potential impacts and do your best to mitigate the negative ones by planting cover crops, rotating your crop families, and maintaining proper pH and organic matter.

All of that said, I almost never recommend tilling at the end of a growing season. The leftover roots from your vegetables can be very helpful in holding your topsoil in place over the winter when the risk of erosion by wind and water is highest. If you need till prior to establishing a cover crop, be sure to do so by early September so you’ve got enough time to establish a good stand before frost.

For further reading, we recommend Soil and Plant Nutrition: A Gardener’s Perspective.

To learn more about soil testing, check out Bulletin #2286, Testing Your Soil.

Trees in WatervilleQ: We need to remove a couple of older trees from the middle of Waterville that are dying. We would like to replace them with a smaller tree that will be attractive and be able to live in the city. The area is 75′ wide by 125′ long.

A: Here are some options for you:

Medium-sized trees:

  • Turkish Filbert, Corylus colurna. It’s hardy with interesting light-colored, rough bark and should grow to 30’.
  • Honeylocust, Gleditsia. “Tough” street tree. Thornless honeylocusts have small compound leaves that cast a light filtered shade. Honeylocusts are medium-sized trees in Maine and are able to grow in difficult sites. Some recommended varieties include ‘Skyline’ and ‘Halka.’ Honeylocusts, due to there branching habit, can often be planted under or closer to utility lines than most medium or large trees with necessary pruning.
  • Korean Mountainash, Sorbus alnifolia. This is a beautiful tree that has a different appearance than the common European Mountainash. The Korean Mountainash has beech-like foliage and bark, white flowers in June, and pinkish-red berries in fall and winter.

Large trees:

  • Ginkgo. Ginkgo biloba is a truly unique tree with fan-shaped leaves and an interesting history. Ginkgos are slow-growing after transplanting but grow well in difficult sites. Cultivars: ‘Autumn Gold’ has a broad, conical form with good Fall color; ‘Magyar’ has an upright form. Non-Fruiting.
  • Oak, Quercus. (Street trees only where ample planting space exists). There are many varieties of native oak including the common Red Oak, Pin Oak, Chestnut Oak, White Oak, and Swamp White Oak. The Swamp White Oak has beautiful glossy foliage, exfoliating bark, and transplants well. Consider upright varieties for smaller narrow spaces.
  • Elm, Ulmus. American Elm, Chinese or Lacebark Elm, and cultivars. Once the most popular of all trees. Dutch Elm Disease (DED) has caused and continues to be a severe problem. New resistant varieties have shown promise in resistance to DED: ‘Patriot’, ‘Princeton’, ‘Pioneer’, and ‘Lacebark’ Ulmus parvifolia. Limited availability. All sorts of sizes and shapes. Fast growing.
  • Zelkova. Medium to large tree. A vase-shaped tree that was hoped to replace the American Elm. Zelkovas are vase-shaped but smaller than elms. Difficult branching angles can cause some problems later on if not pruned correctly. Many beautiful specimens exist in the West End near Danforth Street. (Recommend 1.75” to 2” caliper size for street tree use.)

Q: We recently purchased GrubEx because we have white grubs in the yard and moles tunneling after them, making quite a mess of our lawn. I was telling my fiancé today that I want to do a little more research (regarding toxicity levels and safety) before using the product. Then he told me he already put a little bit out! He put it out this afternoon on a patch of our front lawn, by the gate/door of our vegetable garden, and even in between two raised beds in the garden. I am horrified that it won’t be safe to plant anything in my garden this spring/summer! The only thing I have started outside is beet seeds. They are in the next bed over, about 4-6 feet away from where he applied the GrubEx. I also have onions that are about the same distance away. My strawberry bed is one of the beds right next to where the GrubEx was applied. Aside from the onions, strawberries, and the beet seeds, the garden is pretty much all dirt right now.

A: Based on your description of where the material was applied, I do not believe your actual garden beds were treated and should be safe to plant this spring. As with any pesticide, reading the label thoroughly prior to purchase and then again prior to application is very important for safety and to be sure it is applied correctly to control the target pest. In Maine, we generally do not recommend applying GrubEx until June or early July. You are not controlling the grubs present this spring, but the next generation that would be active later on in the fall and next spring. Applying too early is ineffective. White grubs are a common issue, but the safest thing to do it to just let the moles, voles and skunks eat them and tamp down the tunnels in your lawn as necessary. For now, feel free to plant your raised beds as planned.

Q: We are looking for a Maine Master Gardener to assist with the design, planting, and teaching of our new Community Center Sensory & Pollinator Gardener.

We also have a new playground going in this season, and may welcome some low-maintenance landscaping ideas (growing huts, sunflower huts with morning glories, bean poles or other), edibles or herbs around the playground).

We have a grant to get the garden project started, and would love a skilled Master Gardener to guide us on a knowledgeable design pathway for a perennial and annual constant-bloom and constant-aroma garden.

A: Thank you for your inquiry about a Master Gardener Volunteer to help you with your horticultural plans at the Islesboro Community Center. We have a lot of resources for pollinator gardens and kids’ gardens in general.

I’ll get this in our next MGV announcement early next week. I’ll also let our 4-H staff know, since they may be working on a project on the island as well. I’ll write a draft of the announcement for you to look at and edit soon.

Is this garden to be built this season or next? Much depends on your soil, whether there are weeds/turf currently present, how far down the ledge is, etc. Would you like some soil test kits mailed to you? If so, please send along your address and also the address of the Community Center so I can look at a satellite view of the site.

Q: I would like to know which is the best microclover mix for my area. I live in Jonesport, Maine.

A: The best seed mix for your lawn will depend on your soil conditions and how much shade you have. I recommend taking a look at the Maine Yardscaping Program’s list of grass seed sources to determine which grass species suit your needs, and then contacting a supplier to find the microclover mix that includes those grasses. Generally, locally-owned garden centers are a great bet for carrying species that will work well in your area.

Q: When can I apply milorganite to my lawn and plants? I am in Kennebunkport, Zone 5.

A: I recommend starting with a soil test to see if your lawn and other landscape plants require any additional fertility. If your pH is appropriate and lawn is healthy, you may not need to fertilize at all, particularly if your lawn is more than 10 years old. Well-established sod cycles nutrients efficiently on its own and generally does not require further inputs. Adding unnecessary fertilizers may just become pollution, regardless of the source. Please read Bulletin #2166, Steps to a Low-Input, Healthy Lawn for a more comprehensive look at sustainable lawn maintenance. If your soil test reveals a nutrient deficiency, follow the recommendations included with your results. Milorganite may or may not be appropriate for your yard.

Q: Zone 5, in Kennebunkport, I have afternoon sun on my front porch garden. What shrubs/plants can I put there that are low maintenance?

A: I recommend taking a look at native plants if you are interested in low-maintenance selections. Check out Bulletin #2500, Gardening to Conserve Maine’s Native Landscape: Plants to Use and Plants to Avoid which includes a handy chart of suggested species with their preferred light and soil conditions. Once you have a list of possibilities, visit a locally-owned nursery to choose high-quality plants to install.

ripe peaches on treeQ: How do I prune my 10-year-old peach tree?

A: You can read all about the care of peach trees in Maine in Extension Bulletin #2068, Growing Peaches in Maine. Here is an excerpt on pruning:

Peach trees are typically pruned to have a spreading or vase-shaped canopy but can be trained in any shape or allowed to grow naturally. The vase-shaped training, also called “open center,” is preferred because is prevents the tree from growing upright and thus results in a shorter tree from which it is easier to pick fruit. To achieve the open center shape, prune the main branch at a point just above a side branch and keep four or five side branches. Prune off dead or broken branches. Prune the tree as little as possible in the next five years to encourage fruitfulness. Branches growing back into the center of the tree canopy should be removed each year. Peach trees are mature when they have full fruit production, which is usually 5 years after planting. Mature trees can be pruned annually, which will allow more sunlight to reach the lower branches and will lengthen their lifespan. Small branches on peaches frequently die in winter, and these should be pruned each year.

I also recommend the video The Peach Pruning Blueprint from PennState Extension that gives step by step instructions.

Holes dug in the lawn (left) and white grub (right) under the lawn.
Holes dug in the lawn (left) and white grub (right) under the lawn.

Q: My lawn has been invaded by moles or voles. They began in late summer and have made tunnels everywhere. My grass is dead. What can I do to get rid of these pests?

A: If you have critters digging in your lawn, it is because they are hunting for and eating grubs. The best time of year to treat a lawn for grubs is in August. The adults (Japanese Beetles, June Beetles, European Chafers and Asiatic Garden Beetles) lay their eggs in the lawn’s soil in late July and early August and the newly hatched grubs are relatively small and are pretty susceptible to treatment at that point in time. In later fall and in spring the grubs have dug down deeper and are larger and more resistant to pesticides, so, therefore, treatment is less effective.

Here are links to a UMaine Cooperative Extension White Grub Fact Sheet and one from Cornell Extension, Grubs in Your Lawn (PDF). The Cornell fact sheet mentions some treatments that can be used in September, though they note they are less effective than treating in August would have been.

When using any pesticide make sure you read the label carefully before buying the product, follow all instructions and take appropriate precautions as listed.

Q: I am putting together a raised bed garden, using standard cinder blocks. Initially, I was going to use them for the walls of the raised bed. I plan on using plastic as a barrier to stop alkaline leaching from the blocks into the soil. As I look at the design, I have all these empty holes that are roughly 3.5×3.5×16. Can I line these, fill them with soil, and plant things like summer squash, swiss chard, bush beans, and green peppers? Am I correct in thinking the roots need a volume of soil in which to perform their functions, as long as none of the dimensions of the soil space are too extreme?

A: Cinder blocks are a great material for creating permanent raised beds, but preventing direct soil contact with the blocks may be wise. While I have no Maine-based research on this, the University of Maryland Home & Garden Information Center advises gardeners this way:

“Cement block, cinder block, and concrete block, all are made with cement and fine aggregates such as sand or small stones. Fly ash is also often included. Fly ash is a byproduct of burning coal and so contains heavy metals and other hazardous waste. Labels do not give specific information on exactly what aggregate is used in the manufacture of the block. There is also little research data on this topic. Ultimately, this becomes a personal choice based on your comfort level. If you plan to use block as a raised bed material — and many people do – and you are concerned about potential risks, you could seal the blocks with polymer paint. Or you can choose to use another material you are more comfortable with.”

In lieu of planting food crops in those holes, you might consider planting flowers to deter pests and attract pollinators, such as marigolds and borage.

Pepper plant with yellowing leavesQ: For a couple of years, my peppers have germinated and emerged properly but the first true leaves are very pale with discolored blotches and the cotyledons yellow from the edges inward; they tend to struggle after this point.

In the past, I have tried Epsom salts with no luck. I also tried switching from chlorinated tap to well water. I have considered light damage, salts, poorly mixed batch of soil, pH, Nitrogen, Potassium, Magnesium, and Iron as possible issues but cannot pinpoint what is wrong. In the same exact setup, I have onions, lettuce, wildflowers, and herbs and they all look great!

A: It would be helpful to know what variety you are growing, as they vary in disease resistance. Also, did you save these seeds or purchase them? Peppers can be very finicky, so it is unsurprising that they are behaving a bit differently from the other seedlings you have started. The two things that stuck out to me when you described your setup were the distance of the lights to the plants and your media mix. Seeds should be started in a sterile, soilless media to prevent any disease organisms from attacking the young seedlings. They will not require any supplemental nutrition until after they have at least one set of true leaves. When they start to “look hungry” you can fertilize them with a weak, balanced soluble solution, but any nutrients applied before this can burn the plants. Also, your lights should be set up much more closely to the canopy, especially for the first few weeks. Once they get to be about as big as yours are now, you can transplant the healthiest looking seedlings into larger trays or pots. Check out Bulletin #2751, Starting Seeds at Home for some suggestions of how you might tweak your seed starting protocol.

Q: How do I germinate and grow white spruce tree seeds? I live in Woodstock, Maine.

A: White spruce cones should be collected in mid-August. You will know they are ripe when they have turned from green to pale brown. They will need to be well-dried, either air-dried for about two weeks, or you can use an oven or kiln at 100-120 degrees F for 6-24 hours. The best time to sow the seeds from these dried cones is late fall. They should be sown just 1/4″ deep in a well-prepared seed bed. They will need partial shade for their first year and should be ready for transplanting after two years. For more information, see Growing Conifers from Seed (PDF) from the University of Nebraska-Lincoln and Growing Wisconsin Trees From Seed (PDF) from the University of Wisconsin-Madison.

Q: I have a small hobby farm in Durham and would like to sell some of the excess produce from my garden, as well as eggs and honey at a small roadside farmstand (self-serve, honor system) on our property. Would I need any special licenses or permits to do this?

A: There are no licenses or permits required to sell fresh, unprocessed vegetables. It would be a good idea to check in with your town office to see if they have any requirements or restrictions on setting up a roadside stand, particularly if you have a sign (every municipality treats signage differently). As far as your eggs go, as long as your flock is under 3,000 birds, there are no license or permits, but you do need to follow several rules about selling eggs in Maine including labeling your containers. Whether you need any licenses or permits for your honey depends on what form you are selling it in. If it is raw and in the comb, there are no requirements. Once you process it in any way (even if it’s just extracting it from the comb), you will need to check in with the Maine Department of Agriculture, Conservation, and Forestry’s Quality Assurance folks to see if you need a licensed kitchen to make your product. You can find much more information about selling food products in Bulletin #3101, Recipe to Market: How to Start a Specialty Food Business in Maine. I would also recommend speaking with your local UMaine Extension educator about other considerations, like liability insurance and how likely an honor system farm stand is to work for you.

Q: Is there a difference in Zones 4a and Zone 4b for starting seeds/direct-sow and planting seedlings outdoors? I wish to consider the following plants: summer and winter squash, bok choy, artichokes, and both types of lettuces (head and salad greens).

In addition, is there a date range for each one’s growing season? Also, the date range for the harvesting time?

A: The hardiness zones are most useful for estimating whether your trees and shrubs will survive the winter, and not so much for determining when to start annual seeds. The number of frost-free days in your area is much more important for your vegetable garden. The Northeast Regional Climate Center has a map indicating the average frost-free dates in the region so you can get an idea of when your growing season is and sites like Weather Underground have historical weather data you can search for your town. Many farmers and gardeners keep their own records as well so they have access to hyper-local data when it’s time to make decisions such as these. Once you know your average frost-free date, you can take a look at your seed packets for information specific to the varieties you have chosen. They will always include days to harvest number as well, so you can estimate when you will be picking your veggies, based on your seeding dates. For more general recommendations, there is a chart included in Maine Vegetable Gardening: Keep Your Garden Growing to give you an idea of when to sew and transplant and Johnny’s Selected Seeds Seed-Starting Date Calculator allows you to plug in your own dates and get a customized calendar based on your selections. Of course, other practices like whether you use mulch, row covers, low tunnels, or other frost-protection/season-extending practices will have an impact as well. Oh, and be sure to check out Bulletin #2751, Starting Seeds at Home for all kinds of tips as you get your seeds started!

strawberriesQ: I live in Rockland and would like to grow strawberries in a raised bed. I was planning on a height of 2 – 2 1/2 feet. Will this height cause problems for the plants in the winter? Are they more apt to freeze in a higher bed?

A: It is possible that a very high raised bed like you’re proposing would make June-bearing strawberry plants more susceptible to winter injury. It may be worth a try with a section of your raised bed so you can compare it with an annual system. If you prefer to keep the very high bed, completely understandable for ease of maintenance, consider planting day-neutral varieties. The plants will be more expensive, but you can harvest this season. These would be for an annual system, so you wouldn’t need to worry about over-wintering them. For more information, check out Bulletin #2067, Growing Strawberries.

Highbush Blueberries at the UMaine Gardens at Tidewater FarmQ: How do I trim my blueberries and when? What should I feed them?

A: Highbush blueberry bushes should be pruned every year to produce high yields of good quality fruit. Prune the plants when they are fully dormant during the late winter or early spring (January through March). For the first two years after planting, simply remove any dead branches and all weak, spindly growth. Check out our bulletin, Growing Highbush Blueberries, for a great how-to video and to learn more about how to prune plants that have been established for three years or more.

Three to four weeks after planting blueberries, apply two ounces of a balanced fertilizer (e.g. 10-10-10) or one ounce of ammonium sulfate around each plant. Organic equivalents, such as bloodmeal or composted manure, may also be used. Apply the fertilizer in a circle 15 to 18 inches from the base of the plant. Use the same amount the year after planting. Each year following, increase the amount of fertilizer according to the rates listed in table 2 here.

Monarch butterfly on Asclepias incarnata
Monarch butterfly on Asclepias incarnata, our native swamp milkweed. Photo by Reeser Manley.

Q: I would like to plant a simple Butterfly garden for monarchs — maybe even all milkweed — with students at my school in Freeport. Would starting with milkweed be a workable plan? If so, what kind and how much of it should we start with?

A: There are many resources for this. We suggest (like you seem to know!) to start simply.

There are a number of native milkweed species. I have seeds for three of them, so please let me know if you’d like me to send some for starting indoors and transplanting. Here are some good resources:

You may have a prepared site for your butterfly garden but if not, please let me know if you’d like a soil test kit for creating a new garden. For more information, Testing your soil.

If you’d like to do future work in the realm of horticulture with your students, feel free to bookmark this part of our website, UMaine Cooperative Extension Garden & Yard.

Q: I live in Topsham and I have a very large holly bush (no berries). It is about 20 years old. For the first time ever, this winter the deer have eaten off every single leaf, leaving just the bare shape of the bush. Is there anything I can do to save it?

A: I’m sorry to hear about your holly bush. If there are no leaves left, there is little hope that this bush will survive as it has no way to photosynthesize. Late this winter, many deer resorted to eating species (like holly) that they usually are not interested in to avoid starvation. You can always wait and see if it tries to put out a new flush of leaves this spring, but you may want to begin thinking about what you want to replace it with.

Q: I am looking for an organic treatment to take care of cucumber beetles. Kaolin clay was mentioned, but I was concerned about the affects it would have on honey bees. Would the Kaolin clay mixture work on the cucumber beetles? If so, when and how should I apply it? Is it safe for humans, animals and honey bees?

A: Cucurbits are most sensitive to the feeding injury and potential disease the cucumber beetle can vector when they are very small. Transplanting rather than direct seeding is a good start to prevent the early loss of your plants to this pest. If possible, choose a new location for your cucurbits this year, as the beetles overwinter near where they fed last year. Once your transplants are in the ground, immediately cover them with floating row covers to guard against infestation until flowers bloom. Once you see flowers, be sure to take the row covers off to allow pollinators access. If you see beetles during this time, kaolin clay products (such as Surround) can be used to deter the beetles. This material is not toxic to bees, animals, or humans- it is actually often used in makeup, soaps, and some food products. Be sure to read the label for information on how and when to apply with your sprayer. The article Managing Cucumber Beetles in Organic Farming Systems from includes other tips as well, such as mulching under your cucurbits with straw to encourage natural predators of cucumber beetles.

Q: What is the best date to start tomato seeds for a Western Maine garden (New Portland)?

A: The trick with tomato seedlings is to not plant them too early so you end up with leggy, weak transplants when it’s time to move them outside. You generally only need to start those seeds 5-7 weeks before you expect to transplant them into your garden. In New Portland, I’d estimate that’s usually mid-June, so you could start those seeds around May 4. If you have historically been able to move them out earlier, you can back that seeding date up a bit. Your seed catalogs and packets have a lot of information specific to the varieties you have chosen, so be sure to pay attention to those recommendations as well. You can also check out Bulletin #2751, Starting Seeds at Home for a complete guide to starting your garden seedlings. Have a great growing season!

Q: My question relates to foundation shrubs, are there any that deer may stay away from? I also have a gambrel roof that sends a lot of snow onto the plants. I need to replace broke plants this spring and just don’t know what to put in this time having done this twice already. I live in Standish.

A: Foundations and under-eve areas are tough environments for woody plants. Especially those with brittle wood like rhododendron, or plants that don’t like growing in the dead-sand and curtain drains that surround most homes.

peonyHerbaceous perennials would more likely survive your conditions. They look full, don’t interfere with windows and siding but die back in late fall. Examples: Peonies, actea, larger hostas, catmint, salvia, etc. For accent plants, try purple smoke bush, but cut it back in the spring for colorful new growth in the spring.

But it’s tricky to make recommendations without knowing your tastes and important site conditions like light, shade, and moisture. There are wonderful design books available in larger libraries. This is a great time to look at photos and make a list of plants that would fit your needs. Be sure to choose plants that are hardy to Standish. Plant Hardiness Zone for Maine.
And deer – These lists may help:

Feel free to bookmark our Garden & Yard website where there are many other resources.

Q: I would like to know the secret to raising beets and chard. I never have any success with them. I live in Dresden and have a lot of hard clay. Do we need to test our soil?

A: Yes, a soil test is the first step towards determining what you may need to do to amend your soil. You can stop by the Knox-Lincoln County Extension office in Waldoboro during business hours to pick up your form and boxes, or request them or download them online directly from the Maine Soil Testing Service website.

Q: Where could I find a time chart about when to plant, grow, and harvest vegetables?

A: Here is a planting chart for common garden vegetables in Maine. Harvest dates will depend on which varieties you choose. You can use the seed catalog or seed packets to find the days to harvest to estimate your own harvest dates.

Q: I want to start a wildflower garden. I would like to know what plants are native to Maine and non-invasive. I would also like to plant some milkweed for Monarch butterflies. I live in Winterport, and the area I want the wildflower garden is under pine trees.

A: Native flowers that will grow under pine trees will be a very different species than ones that will grow in full sun. There are many resources for choosing dry shade plants. To give them a more naturalistic look, plant them in drifts, or larger colonies like they would grow in the wild. Here are some resources and quite a bit of reading to help you plan. From UMaine Extension’s Garden & Yard website:

From UMaine Extension’s Garden Pro Answer Book

If you’re interested in the subject of native plants, there are wonderful groups promoting their use. From the Wild Seed Project:

Coastal Maine Botanical Gardens: Visit some of their woodland understory gardens with a notepad and camera to get some great ideas. They have a great display of spring ephemerals.

The Knox-Lincoln Soil and Water Conservation District has an excellent plant sale including native plants. If they are not close by, check out your other SWCDs to see if they have a sale this spring.
Where to buy native plants in Maine: Native plants, a source list.

In the first season, it will be important to water your new plants carefully at the root zone twice a week, depending on rainfall.

Let me know if you need basic information on how to plant perennials and if you’d like us to mail a soil test to you.

Q: We are planning to plant a tree in the spring with our daughter’s ashes. It was recommended we contact our local Cooperative Extension about what nutrients to add to the soil to counteract the toxicity of the ashes. Can you head me in the right direction?

A: Thank you for your question and so sorry for your loss.

It would be good to analyze your site and do a soil test before you add soil amendments for your memorial tree. If you send your mailing address, I’d be happy to send a soil test kit to you. It will give you information about your soil’s existing pH and nutrients.

Based on conversations with an Extension soil scientist, one urn of ashes should not impact a tree’s growth other than a slight chance they may raise the pH a point. A good way around that would be to dig a planting hole that’s quite a bit wider than the root ball. Place the ashes around the outside perimeter of the hole. This way, the roots won’t immediately touch the material until it’s had a few years to leach out.

Here’s a fact sheet with more detailed information: Selecting, Planting and Caring for Trees & Shrubs in the Maine Landscape.

For more information, feel free to book mark our website: Garden & Yard. Look for more ideas under Plants for the Maine Landscape.

Q: As a foundation plant, what is the best Oakleaf Hydrangea to plant under a window in Brunswick, Maine? When should it be put in?

A: Hydrangea quercifolia (Oak-leaf Hydrangea) ‘Sike’s Dwarf’ may be a good one for under a window. It only gets 2-3′ tall and also one of the hardier oak leaf hydrangeas. The Plant Finder at Missouri Botanical Garden has excellent information on many ornamentals, including other hydrangeas.

Brunswick is in zone 5a or 5b, so with protection from wind, ice, and snow, it should be OK after getting established. Please read this information before you buy plants in the spring: Selecting, Planting and Caring for Trees and Shrubs in the Maine Landscape.

Foundation plants: Keep plants at least 3-5′ away from the house so the plant does not interfere with siding and so roots are not in dead sand or interfering with curtain drains. Rain, ice and snow from the roof’s drip line can also be hard on plants. So in general, the foundation area is not always a great place to put woody trees and shrubs. Some herbaceous plants that are shrub-like but which die back every winter (like peonies) can sometimes be a better choice for a foundation area.

I hope this is helpful and feel free to bookmark our Garden & Yard website.

Q: One side of my house has a small garden area that is contaminated with lead. The previous owners of the house had a raised bed there. The site is very dry and hot and we do not want to continue to try to grow vegetables there. What might we do to improve the soil and is there a one-season ground cover that might capture some of the lead? The lead count was not extremely high.

A: Here’s information from the Maine Soil Testing Service about lead in the soil:

Lead is by far the most common contaminant of soils. Lead is very toxic to humans, and children are particularly likely to be affected by lead-contaminated soil by accidentally consuming soil as they play outside. Lead can also be taken up by plants and enter the human diet. We include lead screening in the routine soil fertility test for all soils from gardens, ornamental beds, and turf areas. You will be notified if we suspect your soil may be high in lead. For more detailed information: Lead in the Soil (PDF).

Q: In the past, I have used a landscaping company to mulch my perennial garden. This year I need to try to do it myself. When is the optimal time to mulch in Spring?

A: The best time of year to mulch is when perennials are just emerging. Use a dark bark mulch from a reputable nursery. Mulch can be purchased in bags, but it’s probably best to have it delivered and dumped on a tarp, moving it to the garden with a wheel barrow or trug. To find out how much mulch you need at a 2.5″ depth, use a soil volume calculator.

Unless your soil test says otherwise, there’s no need to use bark mulch that’s pre-mixed with compost or other fertilizers. If you think you do need some added fertility or a soil conditioner for sand or clay, simply side dress each perennial with a few handfuls of bagged compost after cleaning up the area and before applying the mulch. Be sure you don’t bury the crowns of the plants. If you have any woody ornamentals in your garden, be sure you leave space between the trunk and the mulch to prevent rot.

For more information about gardening, feel free to bookmark our Garden & Yard website.

Q: I am trying a small crop of turmeric, as well as doing a larger crop plan for my course in Crop Production. I thought I would try turmeric as New England gardeners are having success growing ginger in hoop houses and turmeric seems like the logical next step. I am having a difficult time finding information on amendments, nutrients, and micronutrients that is specific to turmeric. Do you have that information for turmeric, or can you recommend a resource for me? If not, since turmeric is part of the ginger family, and the information is abundant for ginger, would you recommend following that? There is a soil test for the larger crop plan, and I will be doing one at my home as soon as I can get to the soil, so I will know what my starting point is.

A: You are correct, there are not a lot of research-based cultivation recommendations yet for growing turmeric in high tunnels. As you noted, culture is very similar to ginger, so you are on the right track following those guidelines for now. There is a workshop coming up at Penn State on March 9th, Growing Turmeric and Ginger / High Tunnels that appears to be in-person only, but you might be able to register and even if you cannot attend, perhaps receive the handouts. For some basic culture information for Maine, check out MOFGA’s Growing Ginger in Maine and FedCo’s Growing Guide for Ginger & Turmeric.

Additionally, Ginger and Turmeric Production in High Tunnels (PDF), a presentation from Karen Scott at Oakwoods Farm in Granby, Missouri, includes photos and some of the tips and tricks they use.

Q: I’ve dried a variety of blue corn for cornmeal by hanging it in my cabin. Most all the kernels have become wrinkled, but a few are plump. There is no signs of discoloration. Are they safe to grind or should I pick them out and discard them?

Also in picking, drying, and using popcorn that I’ve grown, some of the kernels were hard and dry, but have a splotchy look, and most all one color. I do think those are spoiled kernels. What do you think?

A: Sorry both of your corn varieties did not cure well. It’s hard to know what conditions caused this, but probably a combination of too much moisture, not enough air flow, and fluctuations in temperature (causing condensation).

Most Extension publications on drying corn are for industrial-scale production. I found this 1975 article in Mother Earth News that describes the process for home gardeners: How To Dry Corn and Grind it Into Corn Meal by Carol Suhr.

Here’s an article from Wisconsin Cooperative Extension about different varieties of corn for drying.

Based on your photos and descriptions, we would not recommend grinding and eating the dent corn or cooking and eating the popcorn because of possible pathogens.

flats of seedlingsQ: A friend who starts seedlings in his home are often leggy by the time he plants them. Do you know what he could do to prevent this or who he could contact for advice on starting seedlings indoors?

A: Leggy seedlings are often the result of insufficient light. Seedlings need 14 – 16 hours of natural or artificial light per day. If using artificial light, the bulbs should be hung between 2″ and 4″ above the tops of the growing plants. Excessively warm room temperatures and over-fertilization can also cause seedlings to put on fast, soft tissue. Lastly, if your friend starts his seedlings too early, or if they are crowded in their containers, this can also lead to legginess. I suggest you refer your friend to the following bulletin #2751, Starting Seeds at Home.

Q: I would like to buy and plant a couple of fruit trees. I do not want dwarf size. These are for birds, deer, and whatever other animals want to use the fruit or trees. I live in New Harbor. Where would you recommend I purchase fruit trees?

3 deer in fieldA: While we cannot recommend one private business over another, we do recommend using a local garden center to source your fruit trees. You can find one on the Plant Something! Plant Maine! website, which lists independent garden centers. Dwarf trees have become very popular, so it may be a bit more difficult to find standard-sized trees, but a local garden center will only carry varieties on rootstocks suited to your area and are likely to get you exactly what you need.

If you happen to have any wild trees on your property, you can learn to encourage them as well. Bulletin #7126, Wild Apple Trees for Wildlife has some tips.

In the spring, be sure to give your new trees a great start by following the best practices in Growing Fruit Trees in Maine.

Q: Will my plants get damaged if I thaw the ground 6 to 12 inches deep with a “ground thawing blanket”? We need to thaw a 3 x 4 foot area for a concrete pad. The plants are iris, tulips, mums, and pink flowers that look like mini carnations. We have the means to pot and protect them for the rest of the winter either indoors or in the garage, which has a 42-degree minimum temperature.

A: While I have never done quite what you are proposing, I do think that if you are able to quickly pot and hold these bulbs below 48 degrees until you want them to begin growing, they should make it through just fine.

Here are some tips on Growing Bulbs Indoors to help you plan for potting them up once the ground has thawed.

Please, let us know how it goes and send some photos along of the process!

Q: What species of milkweed should I plant to provide habitat for Monarch butterflies? I live in Machias, on the northern end of the coast. Will milkweed grow in my area/USDA plant zone?

Monarch butterfly on Asclepias incarnata
Monarch butterfly on Asclepias incarnata, our native swamp milkweed. Photo by Reeser Manley.

A: The species of milkweed that I recommend you plant in your home garden for Monarch butterflies is Asclepias incarnata, Swamp Milkweed. It is native to Maine, and unlike the rhizomatous common milkweed (Asclepias syriaca), swamp milkweed is a clump-forming, self-contained milkweed that stays put. Commonly found in swamps and wet meadows, it grows well in seasonally flooded sites and average garden soils. It is hardy to zone 3 (very northern Maine), grows to a height of 4′ – 5′ and a width of about 2′. It blooms in late summer/early fall and comes in pink and white cultivars. It needs full sun. It might be hard to find in your area, but there are certainly larger nurseries around the state that sell it, and you can probably order it online. Also, on Saturday morning May 25, 2019, we will be having a perennial plant sale at the UMaine Extension Hancock County office in Ellsworth where we will have Asclepias incarnata for sale.

Q: I still have a row of collards in the garden that I can’t remove because they are frozen in the ground. Today I started pulling dead and gone-by leaves off the collards, thinking I could at least add some greens to my compost heap. As I pulled, I disturbed some kind of flying insects (at least a dozen) evidently living on the plants. They looked and flew like mosquitoes, but on closer inspection, their bodies were somewhat thinner (if that’s possible) and their legs were longer. How could they possibly exist, considering the weeks of sub-freezing cold we’ve been experiencing?

Crane fly
David Cappaert,

A: After consulting with our Entomologist, we can offer you the following: There are many species in several families of flies that are cold hardy. Many resemble mosquitoes. There are many in the midge groups, including the Chironomids, which the hardcore fly fishers depend on to give them winter action. Your insect is most likely a winter crane fly. You can find more information at Bug Guide.

Ask the Expert Q&A Archives