Maine Home Garden News – June
In This Issue:
- June Gardening Notes: Edges of Early Summer
- Big Yields on Small Plots: Container Gardening
- Seeing Seeds Differently: Cilantro and Cumin
- Seasonal Sightings: Canada Serviceberry
- Maine’s New Interactive Map for Invasive Forest Pests
- Cucumber Beetles
- Libra Sun Flower Farm – A Certified Pollinator Friendly Garden
- Ask the Expert: Voles and Groundhogs
- Featured Resource: Invasive Plant Lists and Information Sheets
- Maine Weather and Climate Overview
June Gardening Notes: Edges of Early Summer .
By Sandra Mitchell, Penobscot County Master Gardener Volunteer, Maine Master Naturalist
June in Maine arrives like it’s making up for lost time. The garden that looked tentative in May is suddenly lush, the air smells different — warmer, earthier, full of things growing — and the light holds so late into the evening that it’s easy to lose track of time altogether. For Maine gardeners, this is the month when the season stops feeling like potential and starts feeling like reality.
It’s busy in the best way. Here’s what’s worth your attention right now.
Mulch, Moisture, and the Soil Beneath Your Feet
June brings consistently warmer temperatures, and with them, the first real test of your soil’s moisture management. This matters most for vegetables, tender annuals, and anything planted in May that is still getting established. A light layer of mulch (see Ask the Expert question)— one to two inches over bare soil — slows evaporation, moderates soil temperature on the hot afternoons that are starting to arrive, and suppresses the weeds that are very much still trying to get ahead of you (and likely have already gotten ahead of me!).
Water deeply and less frequently rather than a little every day, and do it in the early morning if you can. Foliage that goes into the night wet is foliage that is asking for trouble, (see Bulletin #2753, Managing Diseases in the Home Garden) especially later in the season.
The Pest Parade Begins
June is when you start to see who else has been paying attention to your garden, and not in a good way, unless you like studying bugs (while they consume your plants!).
Flea beetles make themselves known on leafy greens — you’ll see the tiny, scattered shotgun-hole damage on arugula and brassica leaves before you ever spot the beetles themselves. Delayed planting or setting out larger, more established transplants can help you sidestep peak flea beetle pressure, and row covers placed immediately over seeded beds or young transplants offer a reliable physical barrier.
Aphids cluster on tender new growth, favoring roses, evening primroses, and vegetable shoots – and my beloved milkweeds. A strong spray of water knocks them back surprisingly well, and it’s worth trying before reaching for anything stronger.
Slugs are very much a June problem in Maine, especially after a wet spring — check under boards, pots, and low-lying foliage in the early morning or evening if you’re seeing mysterious damage at the base of plants. A half buried can of beer in strategic places works well for me, and beats hand-picking them – unless you have chickens. They are definitely a poultry delicacy!
Colorado potato beetles appear this month too, and the time to deal with them is before populations build, not after. Check the undersides of potato leaves for the distinctive orange egg clusters. Since potatoes don’t require pollination, fine mesh netting makes an easy, effective barrier — just make sure it’s secured before adults have a chance to establish.
The single most effective pest management tool you have is ten minutes a day walking your beds with your eyes open. Problems caught small stay small.
Pollinators and What’s Actually Blooming Right Now
The edges of the garden are doing something interesting in June, and it’s worth stopping to notice.
Bumblebees, flower flies, and a whole community of smaller native pollinators you may not have a name for are actively foraging now, and they’re telling you something about what’s blooming and what’s setting fruit. Watch which crops they’re visiting — squash and cucumbers that aren’t getting pollinator attention early in the season often disappoint at harvest time. Consider joining a community science program, such as Project GNbee, to document the pollinators in your area – no identification skills needed!
In Maine’s roadsides, fields, and wild edges, June’s signature native wildflowers include blue iris (Iris versicolor), bush honeysuckle (Diervilla lonicera), boneset (Eupatorium perfoliatum), wild strawberry (Fragaria virginiana), fleabane (Erigeron annuus), and carpets of bunchberry (Chamaepericlymenum canadense). Milkweed (Asclepias syriaca) is pushing up and beginning to bud now — the monarchs won’t be far behind. Worth noting: the lupine (Lupinus polyphyllus) blanketing Maine’s roadsides are not native, and despite their beauty, they offer little in the way of ecological value to local wildlife.
If you have room in a border or an awkward corner of your property, a patch of native wildflowers planted now will pay dividends in pollinator activity for years. Plants that do well here include wild bergamot (Monarda fistulosa), native coneflower (Rudbeckia laciniata), and Canada windflower (Anemone canadensis) — all genuinely useful to pollinators and all willing to take care of themselves once established. You might even find that you like them better than the showy non-native flowers – and your garden will, too!
What’s Blooming and Fruiting in the Trees and Shrubs
Take a walk around your property and nearby natural areas this month — the shrub layer is one of the most rewarding things to watch in June.
Rhododendrons and azaleas are at their peak in shaded woodland edges, often a startling burst of color among hemlock trunks and understory ferns. Wild roses — both Rosa palustris in wetter spots and Rosa carolina on drier ground — are beginning to open, and their fragrance on a warm June morning is one of the genuinely good things about gardening in Maine. Mountain laurel (Kalmia latifolia) is flowering now in areas with rocky sandy soils, and elderberry flowers are just developing into flat-topped white clusters along roadsides and stream edges. Serviceberries have already finished flowering — that was May’s show. By June the berries are forming, and if you’re growing them in the landscape, the birds already know this before you do.
Paying attention to bloom timing in the trees and shrubs around you is one of the habits that quietly makes you a better gardener over time. These plants are tracking the same temperatures, moisture levels, and light your vegetables are, just on a larger scale.
The First Real Harvest
By mid-June, the garden starts giving back.
Peas are one of the best pleasures in June — they come in fast once they start, and they don’t wait for you. Pick them young, eat them the same day if you can, and keep picking consistently because pods left on the vine signal the plant to stop producing. The tender pods are amazing in salads and stir fries. Radishes, baby greens, and the first herbs — chives, parsley, the early basil if you were brave enough to plant it — are all ready now. A dash into any soup, salad, or sandwich adds taste, but nutrition, too.
Harvest in the cool of the morning when moisture content is highest and flavor is at its peak. There’s a particular satisfaction to bringing in food you grew, and it doesn’t diminish no matter how many seasons you’ve been at this.
June Moves Quickly
The thing about June in Maine is that it doesn’t stay (unlike some other months, like….January?!). Before you know it the solstice has passed and the days are already, almost imperceptibly at first, getting shorter again.
The gardeners who get the most out of this month aren’t necessarily the ones working the hardest. They’re the ones paying attention — to what’s ready, what’s struggling, what the pollinators are visiting, what the shrub layer is doing at the edge of the field. Your garden is embedded in a larger landscape that’s running on the same seasonal clock, and the more you notice that connection, the more sense your own garden starts to make.
Enjoy it. June is one of our pinnacle months in the garden.
Big Yields on Small Plots: Container Gardening
By Carrick Gambell, Urban Agriculture Professional UMaine Cooperative Extension and Natural Resources Conservation Service
While growers may dream of tending a flat, sunny plot with well-drained loamy soils, this is not always a reality. Rural growers often contend with rocky soils, heavy clay, steep hillsides, or shade from trees. Growers in towns and urban areas often have limited access to open yards or opt to avoid potential contaminants in soil. Sometimes the sunniest growing space is a front driveway or porch. Growing in containers is an excellent option for those seeking an alternative to a traditional in-ground garden or raised bed. Containers can be moved easily, filled with a reliable growing medium, and can provide accessibility to gardeners with limited mobility. The materials can be affordable, and the installation process straightforward. Growers interested in container gardening should start by considering the appropriate materials, size, water management, and vegetable varieties.
Just about any container can be used for gardening. Plastic and ceramic pots from garden and hardware stores are dependable options because they have been designed for planting. Barrels, window boxes, and hanging baskets are also great candidates, especially for growers hoping to add an aesthetic flair. Growers should avoid containers that have been painted on the inside or that may leak toxic chemicals, such as old tires or treated lumber. Five gallon buckets that are labelled “food safe” can be re-purposed for container gardens.
The container should be deep and wide enough to support the crop roots when they are fully developed. A basic principle of container gardening is that the larger the container, the easier to manage. Container gardening in general requires more regular, intensive watering, and the soil in a small pot will dry out much faster than a larger container. Dry, hot soils will stress the roots and ultimately damage the plant. Another issue with smaller containers is that if the soil dries out, the container is much lighter and easier to blow over in the wind. A larger container may be heavier and more challenging to move, but it will hold water for longer and withstand strong winds and storms.
Whatever container the gardener chooses should have adequate drainage. For re-purposed structures like five gallon buckets, growers will need to drill holes to allow for drainage. If the container is going to sit directly on an impermeable surface like a deck or a patio, drill the holes on the sides, ½ inch from the bottom, to increase the drainage and prevent waterlogging. Water should be allowed to drain freely from the container and not collect in a saucer, as these saucers can facilitate the spread of fungal disease and mosquito larvae.
Many of our favorite vegetables grow happily in containers. Plant breeders have developed miniature varieties that demonstrate high yield and compact growth habits. Growers can experiment with patio baby eggplants, lunchbox peppers, or determinate tomatoes. Bush beans and peas can be planted densely in a container and generate surprisingly large harvests. Zucchini and summer squash are slow to vine and can thrive in the warmer, nutrient-rich growing media in a container. Herbs are straightforward to grow and convenient to harvest for a quick burst of flavor with dinner.
Apartment dwellers and folks with nontraditional yards can still eat well from their gardens, even if their garden consists of containers on a porch.
References:
- Durham, R. E. and D. B. Hill. Gardening in Small Spaces. Lexington: University of Kentucky Cooperative Extension Service
- Hopkins, A., Coffin, D., and Wertheim, F. Container Gardening Series: Growing Vegetables in Container Gardens.
Seeing Seeds Differently: Cilantro and Cumin
Introduction by Lynne Holland, Horticulture Professional; plant descriptions by Citlalli Constantino, Master Gardener Volunteer
Finally, the threat of frost is past. Hot days mean quick meals and fresh foods from the garden. Herbs are one way to take meals to the next level. Certain herbs and spices are also the signature for some styles of cooking. Here are Lali’s take on two relatively easy-to-grow herbs. One often appears in Mexican cooking, and the other is a bit of a surprise.
Cilantro (Coriandrum sativum)
Cilantro is related to carrots, celery, and parsley, meaning that it is umbelliferous. It is important to note that cilantro is what we call the leaves and coriander what we call the seeds. Both show up in cooking in various cultures.
This delicious, aromatic, and citrusy herb is one of the easiest to grow. The seeds can be scattered in regular soil in the spring; they don’t do well being transplanted. It is one of those fussy plants that have sensitive roots, so if started indoors, at least use one of those biodegradable pots to minimize root disturbance. It grows better in full sun and if you let it drop seed you will likely find many volunteer plants in future years. It grows well in dry and humid conditions, but it bolts easily during hot spells, which is why it is suggested to sow seeds constantly during the season. The seeds of this herb can be saved, and next year the gardener can start the process again. That’s why I recommend getting heirloom or open-pollinated seeds even when the “slow bolt” sounds tempting.
In Mexican culinary culture, cilantro is used every day, in all kinds of dishes, soups, tacos, ceviches, appetizers, street food, salsas, beans….I could name easily 20 recipes that incorporate cilantro.
This herb is often mistaken as being Mexican in origin, but cilantro was brought to Mexico by the Spanish after they colonized Mexico. The Spanish got it from the Middle East culture, which is why cilantro is present in Indian, Thai, Moroccan, Turkey, Greek, Irani, and Egyptian cuisines. According to various culinary history websites, cilantro was found in the Egyptian tomb from Ramses II and is also mentioned in Persian literature from 3000 B.C.E.
Cilantro is one of the kitchen herbs that is a must in any garden except for those of gardeners who have the 6A2 gene, which affects the taste of some compounds. These gardeners won’t find cilantro nice and aromatic…in fact, the opposite, cilantro will be soapy and disgusting. Have you heard someone saying that cilantro doesn’t taste good??
Sources:
McCormick Science Institute
Gobierno de Mexico
Black cumin (Nigella sativa)
One of the most fascinating things about gardening, from my personal experience, is all the biology, botany, and science behind it. I assume this is because my real passion was to be a biologist, but I ended up being a cook. I mention this because when I was doing my research about black cumin, I was wondering why my seedlings were very similar to my love-in-a-mist seedlings, and then I read the scientific name: Nigella sativa. I realized that black cumin is not the cumin spice that is present in some Mexican dishes, but a close relative to the beloved flowering annual. The traditional culinary cumin’s scientific name is Cuminum cyminum. A big “Wow!” came from my mouth as it does often during my gardening journey.
Black cumin is an annual, from the Ranunculaceae family, compared to Cuminum cymium, which is from the Umbelliferae family. It can be started indoors or sown in mid-spring straight in the kitchen garden. It needs full sun, fertile and well-drained soil, and it is recommended to succession plant every 3 to 4 weeks for continuous flowers and seed harvest.
The uses for this spice are very similar to those of poppy seeds, like in bread and cakes (I’m imagining a loaf covered with black cumin seeds). It is also used for its medicinal properties and attracts pollinators. If you want to know more about the cumin that is found in many Mexican dishes, this information from the North Carolina Extension Gardener’s Plant Toolbox is a good reference.
Other names for the black cumin are nutmeg flower, black caraway, and roman coriander. What I can say now is that I can’t wait to see these little blooms, find out the aroma, and add these seeds to my winter baking.
Reference: Pinetree Garden Seeds
Lali’s Bio
Mexican cook, with experience in different culinary areas, from restaurants, cafeterias, cruises, summer camps, college culinary art instructor, nowadays working at the school nutrition department in a cafeteria from an elementary school in Lewiston, I’m a Master preserver which has gave me the opportunity to volunteer and learn from all those experiences, I’ve also gave some classes at the Lewiston Adult education.
I’m passionate about gardening, horticulture, farming, bird watching and everything related to nature. I fell in love with Maine and a Mainer, a naturalist in spirit.
Seasonal Sightings: Canada Serviceberry
By Maine Audubon Native Plants Program Coordinator Jocelyn LaClair
Often an understory tree in established forests, Canada serviceberry (Amelanchier canadensis) usually grows as a multi-stemmed shrub up to 20 feet tall, a bit smaller than other serviceberry species. In spring, this tree has showy and fragrant flowers with five long white petals. Serviceberries bloom around the same time, but Canada serviceberry is usually a week later than the other species. It has somewhat wide and rounded leaves that are finely toothed, and in June, delicious red to purple fruit emerges for a short period of time before being devoured by animals. The fall foliage is spectacular, with leaves turning red and orange as the weather cools.
The wide range and large cultural importance of this species means that it has plenty of common names. It is known as Juneberry because of the fruits that ripen in June. It is also called shadbush or shadblow, because the spring blooms are a cue to the Wabanaki that shad are returning to coastal rivers. These blooms were a different cue to European settlers, who noted that the ground had finally thawed enough for burial services and therefore named it serviceberry.
At least 35 species of birds devour serviceberries, well-timed for their breeding season. Mammals such as chipmunks, squirrels, beavers, and bears also snack on the fruit. Serviceberry is also an important browse plant for deer and moose, and the prolific flowers in spring are a crucial food source for native bees.
Other June signs of wildlife to look for
- Watch for milk snakes—rarely seen because of their nocturnal habits—as they seek sheltered spots to lay their eggs.
- Adults of many species of moths and butterflies, like white admirals, are flying now, looking for mates and host plants to lay their eggs on. White admirals in Maine usually lay their eggs on birch species like yellow birch.
- Red columbine and bush honeysuckle are blooming now. These native wildflower species grow well on forest edges and rocky areas like outcrops and stone fences, and are an important early nectar source for Ruby-throated Hummingbirds.
Maine’s New Interactive Map for Invasive Forest Pests
The Maine Forest Service has launched a new interactive map to help people see which forest pests have been detected in their communities.
The Invasive Species Dashboard displays detections of several major forest insect species and diseases at the town level, providing a quick way to check what is present in an area. Whether you are a landowner, arborist, municipal official, or simply interested in the health of Maine’s forests, the map provides an accessible starting point for understanding local risks.
The dashboard is updated regularly by Forest Health and Monitoring staff as new detections are confirmed, ensuring that the information remains current and more relevant than static distribution maps. Users can click on individual towns to view the year a species was first detected and are encouraged to contribute their own observations of these species in new towns by filling out the online reporting form.
Explore the dashboard by visiting maine.gov/forestpests.
For more information on individual pests, including identification, impacts, and management options, visit the Maine Forest Service Forest Health and Monitoring website.
Cucumber Beetles
By Patti Elwell, University of New Hampshire Master Gardener Volunteer, Rockingham County
If you are finding that cucumber beetles are becoming worse each year in your garden, you are not alone. One particularly annoying trait of this pest is its ability to live in and expand its residence in your garden. They can easily overwinter in soil, dead vegetable debris, and heavy mulch. If you ignore their presence, they are likely to increase over the years.
Whether striped or spotted, cucumber beetles cause significant damage to not only cukes, but also squash, zucchini, pumpkin and melon. The adult beetles destroy crops by chewing leaves and reproductive parts while the larvae feed on plant roots. Additionally, they are a vector for diseases such as bacterial wilt, cucumber mosaic virus and squash mosaic virus. These diseases can spread rapidly and affect yields or even kill the plants.
As with most pests, the best way to manage cucumber beetles is to start by understanding their lifecycle. They lay eggs midsummer in the soil around the base of host plants and hatch into larvae after about 10 days. Larvae develop and feed on roots for 2-6 weeks followed by a 7-10 day pupal stage after which they emerge from the soil as adults. The adults overwinter in plant debris and emerge in early to mid June – right when young, tender plant leaves are sprouting. The newly emerged adults feed on cotyledons (first baby leaves), leaves, and stems of the new plants.
So what can gardeners do to protect their plants?
Immediately cover the area where you have planted seeds or young plants. Covering gives the plants a chance to grow stronger until they produce both male and female flowers. The cover needs to be removed, however, for pollination when both flower types have developed. You might try to protect your cucumbers from pests by growing them under row cover from planting until harvest. To do this, you would need to use varieties that are parthenocarpic or self-pollinating, and they will set fruit without the need for pollinators to move from flower to flower.
If left uncovered, begin looking for the insects every few days as soon as your plants go in the ground. Pick, remove, and destroy any cucumber beetles you see. Dedicate a small hand vacuum to collect insects more efficiently.
Planting a “trap crop” that tends to be more highly attractive to a pest can help aggregate populations into a tighter area where they can be more easily managed and lured away from the desired crops. ‘Blue Hubbard’ squash is a good trap crop for striped cucumber beetles.
Lacewing and ladybug larvae are known to be predators of cucumber beetle eggs and larvae. Plants rich in pollen that bloom throughout the season will encourage these beneficial insects to live and reproduce in your garden. Flowering herbs, such as dill, fennel, cilantro, yarrow, sweet alyssum, and marigolds, will attract lacewings, ladybugs, and other helpful pollinators. Keep in mind that beneficial insects alone will not provide adequate control.
If you have tried these non-chemical control methods but are still having difficulty managing these pests, consider using some of the suggested pesticides outlined in the following Maine-based resources:
Maine Organic Farmers and Gardeners
UMaine Cooperative Extension Pest Management Fact Sheet #5038
If you decide to apply pesticides, always follow the label instructions and do your best to only purchase what you need.
Libra Sun Flower Farm – A Certified Pollinator Friendly Garden
By Susan Joakim, York County Master Gardener Volunteer
Carolyn Maul is as passionate about her gardening as she is about her artwork. She sees the land as a writer sees a blank piece of paper, or a painter, a blank canvas. Something that is ready for her creative, artistic flair, and like any artwork, gardening doesn’t always come easily.
Carolyn has been a lifelong gardener with experience across the country. She bought her property in Hollis, New Hampshire, three years ago with gardening and her artwork in mind. The land was scared, gutted, injured. Reminiscent of how her soul was feeling at the time. The land had been used as a dumping station for all things toxic, burn piles scattered the area and the invasive plants (80% of the property), such as bittersweet, were, well, unreasonable. However, she does marvel at bittersweet’s amazing ability to survive. To successfully rid the area of it, she must remove all the roots and replace it with something comparable such as bee balm with its dense roots that leave little space for anything else. Her plan is to take the scarred land and make it an ecological sanctuary, a landscape beacon for others to enjoy. As a steward of the land, she feels solely responsible for what happens to it, a role she takes seriously.
She first heard about the Pollinator-Friendly Garden Certification from a friend, an avid gardener who had a sign in her yard. When she read through the application for the certification, she realized it was a great learning experience and would show her all the many plants, trees, or shrubs she could use.
Carolyn spends every day, weather permitting, outside trying to undo the damage that had been done to the property. Getting the Pollinator-Friendly Garden Certification was her way of saying she’s on the right path. She works hard to avoid using chemicals, and after three years, she’s reduced the amount of bittersweet by half. She knows that maintaining it can take years, but she feels it’s worth it.
For Carolyn, gardening is a gateway to her artwork. She creates ecoprints that require plants with high levels of tannins and dyes and so she is mindful of the specific flowers she adds to her summer gardens. Her gardens produce material for her to dry and freeze, such as flowers, leaves, and berries, which enables her to work on her art throughout the long New England winter. Creating ecoprints is similar to gardening, it takes patience, time, many steps, and one never quite knows how it will all turn out.
The Libra Sun Flower Farm sells cut flowers in a farm stand out front. It’s a popular spot, and she sells out fast. She has a cut flower garden that, in contrast to the rest of the property, is in rows, measured, counted, and planned out. She sells the cut flowers in repurposed vases and also uses the flowers for her ecoprints. She plants with an eye toward how strangers would see the place, drawing them down pathways leading to small beds tucked away in nooks and crannies. She has a two-season greenhouse and envisions the property as a place where people can come for special occasions, photo shoots, learning, meditation, weddings— all things that will enhance their lives.
Carolyn is especially proud of the perennial labyrinth she has built on the property. She has always been enamored of circular labyrinths with one continuous path that leads to the center, which are designed for reflection, contemplation, and meditation. She was raking out one of the burned areas when she began crying. “How can I heal this small part of the earth along with myself?” she asked. A great deal of healing was needed for both. She had an epiphany, what better way to heal than through a labyrinth? She designed hers after the pattern used in 1206 at Chartres Cathedral in Paris, France. Using soil and rocks from the property for the pathways, the labyrinth is about 80 feet in diameter and takes about 5 minutes to get to the center. Lined with perennials, not shrubs as are typical with labyrinths, the walker is blessed with a plethora of colors and varieties of flowers. It has been an exercise in learning as she has experimented to see what plants work in the area. She grows native perennials from seed but must be mindful of what she plants since the area is far from a water source. Her property is surrounded by forest, so she is aware of the morning and evening shade that it provides the plants.
Carolyn is a Libra (hence the name) and chose the name Sun Flower (not Sunflower) because she likes lots of flowers and the diversity they provide. She shares that climate change has influenced her gardening. She can’t have a rain garden anymore, but she has adapted by using rain barrels and choosing plants that are successful in her specific area. She has great faith in plants’ ability to adapt over time. Year one, she was challenged with slugs, year two, jumping worms (Amynthas agrestis), and this year, she’s going to tackle the vole problem. It’s hard to make permanent changes, but she, like her plants, is resilient and determined to make it work.
Like many gardeners, Carolyn has an unspoken agreement with the land, I heal you as you heal me.
Learn more about Carolyn and the Libra Sun Flower and Labyrinth Farm.
Ask the Expert: Voles and Groundhogs
“How do I get rid of voles and groundhogs in my garden?”
Answer by Jonathan Foster, Horticulturist, University of Maine Cooperative Extension
I’m very sorry to hear about the groundhog/woodchuck and vole issues–they can be quite a headache.
Please take a look at the following resources:
State of Maine “Got Pests?” series page on voles
University of Minnesota Extension page “How to manage vole damage on lawns, trees and shrubs”
Reducing cover by minimizing debris and reducing mulch depth can be helpful, as can surrounding your raised beds with narrow gauge chicken wire (you can place stakes around the inside for structure and staple the bottom of the wire to the inside of the bed sides) to prevent their entry. If you are able to locate any holes or runs, mouse traps baited with something tasty can be very effective. Voles have a very high reproductive rate and are able to recoup losses pretty quickly, so persistence with multiple strategies will probably be essential to protecting your garden. If you ever add more raised beds, I recommend stapling chicken wire across the bottom of the bed before adding fill–this will give you another layer of protection from their invasion of your planting space.
State of Maine “Got Pests?” series page on woodchucks
Cornell University Extension Woodchuck fact sheet (pdf)
Keeping groundhogs/woodchucks out of your garden will almost certainly require fencing if you have a healthy specimen and a nice garden. They are voracious, persistent, and not easily deterred from a fresh buffet. Fencing should ideally be about 4 feet tall. The bottom 10 inches should either be buried straight down or bent at the soil line at a right angle and partially buried. Alternatively, protecting lower growing crops that don’t require pollination by covering with hoops covered in lightweight row cover can sometimes be enough of a physical barrier to deter them from feeding.
That said, groundhogs are great candidates for humane live traps. We had excellent luck using these traps with kale as bait. You will then, of course, have to formulate a plan for dealing with the rodent once trapped–please don’t release them anywhere onto another property without clear permission from the landowner. If you are less of the catch-and-release type of gardener, a local wildlife officer or exterminator can often provide alternative options.
There are also rodenticides available if you reach the end of your rope and are considering chemical interventions, but they will be toxic to any other mammals that consume the bait as well. I would recommend reaching out to a Maine-licensed pesticide applicator to discuss the best options for targeting the pest in question while keeping the garden produce safe for consumption.
Featured Resource: Invasive Plant Lists and Information Sheets
Whether you’re planning your spring planting, managing land, or trying to identify something that’s quietly taking over a corner of your yard, Maine has some important invasive plant resources worth keeping at your fingertips.
The Maine Department of Agriculture, Conservation and Forestry (DACF) Horticulture Program maintains three regularly updated invasive plant lists, developed in collaboration with a stakeholder committee. Each list links directly to biology and management guides for specific plants, making them useful whether you’re actively dealing with an invasive species or just doing your homework before buying something new for your landscape.
The Do Not Sell Invasive Plant List covers terrestrial species that are illegal to import, export, buy, sell, or intentionally propagate. If you’re a gardener, landscaper, or nursery shopper, this is the list to check first. While sellers should not be offering these plants, they can sometimes slip through the cracks, so it’s good to be informed. Knowing what’s prohibited can save you from inadvertently contributing to a serious ecological problem.
The Watch List flags plants that don’t yet meet the threshold for the Do Not Sell list but are being closely monitored. These can still be sold without restriction, but if you’re someone who thinks long-term about your land, this list is a smart preview of what may become a bigger issue down the road.
Plants of Special Concern identifies species that may be invasive depending on habitat. There is currently only one plant on this list: Rosa rugosa. They can still be sold but require special labeling.
Finally, the DACF Maine Natural Areas Program’s Advisory List rounds out the picture. Though it’s not a regulatory tool, it’s invaluable for land managers, naturalists, and engaged gardeners who want a fuller picture of plants that haven’t yet come under formal regulation but still warrant attention.
Return to these lists when you’re planning a new bed, buying from a nursery, noticing an unfamiliar plant spreading on your property, or helping a neighbor identify what’s growing along their fence line. The more Mainers who know these lists, the better equipped we all are to protect the landscapes we love.
Maine Weather and Climate Overview
By Sean Birkel, Assistant Extension Professor, Maine State Climatologist, Cooperative Extension, Climate Change Institute, University of Maine.
Monthly Recap: Average temperature for May (based on data May 1–27) was above normal in Portland and near normal in Bangor and Caribou. However, the first two weeks of the month were on the cool side, and morning temperatures on May 8–9 and 12–13 dropped into the low to mid 30s Fahrenheit across much of the state (colder across north and west), causing frost in some areas. A warm wave then developed, peaking May 19 with daytime high temperatures ranging from the mid 80s to around 90°F across the southern half of the state. Portland set a daily record of 92°F, which ranks among the hottest for May (for example, the daily record maximum temperature for May 18 is 93°F, set in 2017). This heat wave was followed by a pronounced cool wave that brought record or near-record daily minimum temperatures on May 22, especially across central and northern Maine where morning temperatures ranged from the low 30s to mid 20s, respectively. Precipitation for May was generally near to above normal statewide.
Drought Update: Recent beneficial rainfall has lessened drought across Maine. However, significant precipitation is still needed to restore conditions to normal, especially for replenishing lingering groundwater deficits from last year’s dry summer and fall. The latest U.S. Drought Monitor area rankings for Maine are 27% no drought, 35% abnormal dryness (D0), 36% moderate drought (D1), 2% severe drought (D2) (see map below). Additional information is available from the Northeast Drought Early Warning System Dashboard.
Outlooks: The 1-month outlook for June shows equal chances of above or below normal conditions for both temperature and precipitation. The 3-month outlook for July–September shows above normal temperature and above normal precipitation. The NOAA Climate Prediction Center reports neutral conditions across the east-central equatorial Pacific Ocean, and that El Niño is likely to emerge by July and continue through winter 2026/27. Warm ocean temperatures and moisture released into the atmosphere during El Niño tend to produce more weather extremes than usual.
Maine Statewide 2026 Temperature & Precipitation Rankings
From Norther Center for Environmental Information: Climate at a Glance
- May: Monthly summary not yet available
- Apr: 32nd Warmest (above average), 28th Wettest (above average)
- Mar: 34th Warmest (above average), 58th Driest (near average)
- Feb: 52nd Warmest (near average), 2nd Driest (much below average)
- Jan: 54th Warmest (near average), 28th Driest (below average)
For additional information, including historical temperature and precipitation data, weather forecasts, and seasonal climate outlooks, visit the Maine Climate Office website.
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Maine Home Garden News was created in response to a continued increase in requests for information on gardening and includes timely and seasonal tips, as well as research-based articles on all aspects of gardening. Articles are written by UMaine Extension specialists, educators, and horticulture professionals, as well as Master Gardener Volunteers from around Maine. The following staff and volunteer team take great care editing content, designing the web and email platforms, maintaining email lists, and getting hard copies mailed to those who don’t have access to the internet: Abby Zelz*, Barbara Harrity*, Kate Garland, Mary Michaud, Michelle Snowden, Naomi Jacobs*, Phoebe Call*, and Wendy Robertson.
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University of Maine Cooperative Extension is an equal opportunity institution and provider committed to nondiscrimination. For more information, visit extension.umaine.edu/nondiscrimination.