Maine Home Garden News June

In This Issue:

• June Is the Month to . . .
• Hero Hover Flies
• Pollinator Ponderings: Let’s Talk Pollinator-Friendly Annuals
• Chelsea Chop for Native Plants
• Invasive Plant Educational Workshops
• At-Home courses for Maine Gardeners
• Bird of the Month: Eastern Phoebe
• Maine Weather and Climate Overview
• Ten Things to Know About Emerald Ash Borer in Maine

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June Is the Month to . . .

By  Kate Garland, UMaine Cooperative Extension Horticulurist

Thin fruits to encourage them to produce more consistently from year to year.

Biennial bearing—producing a heavy crop one year followed by little to none the next—is common in fruit trees, as they naturally redirect energy to rebuilding resources after a high-yield season. Removing a portion of your crop before they develop encourages plants to produce higher quality fruit and reduces strain on the health of the tree.

Water.

While it may seem like a pretty straightforward garden chore, insufficient, excessive or improper watering methods are often the culprit behind a lot of issues gardeners encounter. Aim for 1¼–1½ inches of water per week, water deeply rather than frequently, and apply water directly to the soil—not the foliage—to prevent disease. Consider using tools like rain gauges or drip irrigation for efficient moisture management, and if you prefer to water by hand, treat yourself to a high-quality hose, watering can, or watering wand to make it a more pleasurable task.

Plant warm-season crops.

If you haven’t already, now’s the time to plant tomatoes, peppers, eggplant, basil and other tender annual plants. Seedlings planted in May that might have suffered from exposure to cooler temperatures may need to be replaced with new ones if you’re noticing signs of cold damage.

Install supports for vegetable and ornamental plants before they get too big.

If you’ve struggled with plant supports in the past, don’t be afraid to try something new! Here are some terrific ideas for tomatoes.

• How To Grow Tomatoes: Staking Learn how to stake tomatoes, remove suckers, and increase fruit production.
• How To Grow Tomatoes: Trellis Learn how to build a tomato trellis, how to remove suckers, and how to prune your tomato plants.
• Caging Individual Tomato Plants Learn how to handle and cage tomatoes in your home garden and what kind of caging to use.
• How To Grow Tomatoes: Basket Weave Learn how to basket weave with tomatoes and why this process works well with both determinate (bear their crop all at once) and indeterminate tomatoes (bear fruit over the course of a season).

Don’t let a tick make you sick.

Even though May was Lyme Disease Awareness Month, it’s always a good time to stay informed about ways to prevent exposure to tick-borne diseases. Bookmark UMaine’s tick lab website so you can be prepared if you or a loved one has an encounter with a tick this season.

Start seedlings for later planting.

Vegetables such as lettuce, cabbage, broccoli, kale, and cucumbers can be direct-sown in the garden, but starting them in pots often makes monitoring easier and helps protect young seedlings from insect and animal damage. Soil blocking (Review February 2023 MHGN-article 1, Featured Tool: Soil Blocker) is a fun, eco-friendly way to start seeds without relying on plastic cell packs, which can be tricky to keep evenly watered.

Direct sow annual flower and herb seeds.

It’s not too late to sow annual flower and herb seeds directly into your garden. Varieties like zinnias, cosmos, sunflowers, larkspur, love-in-a-mist, calendula, bells of Ireland, bachelor’s buttons, ammi, basil, dill, cilantro, and shiso all thrive when planted straight into the garden bed.

“Think first, spray last.”

This timeless tagline from the Maine Board of Pesticides control says it all. If you suspect a disease, insect, or other issue is affecting your plants, be sure to know what you’re dealing with before applying any pesticides. UMaine’s Home and Garden IPM page offers photo galleries and links to information about a wide array of insects, diseases, and other creatures frequently found in Maine.

Grow a little (or a lot) to donate.

Maine has the highest food insecurity rate in New England and ranks 29th nationwide. Since 2000, UMaine Extension’s Maine Harvest for Hunger (MHH) program has donated over 4 million pounds of fresh produce to hunger relief agencies. By engaging gardeners, farmers, schools, and civic groups to grow and give, MHH makes a real impact. Whether it’s a bag of beans or a crate of cucumbers, every donation helps. To find where to donate or how to get involved, visit our website or contact your local Extension office.

Transplant volunteer seedlings.

Hints of last year’s garden often pop up in the form of dozens, if not hundreds, of tiny seedlings if you let your plants go to seed. Cosmos, dill, poppy and coneflower are just a few examples of this great source of “free” fillers for empty garden spaces. To successfully transplant volunteer seedlings with minimal shock, move them when they’re small (1–2 sets of true leaves), handle them gently by the roots or leaves, and choose overcast or rainy days for transplanting; if needed, temporarily pot them in a protected area until their final spot is ready.

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Hero Hover Flies

By Hannah Mullally, U.S. Fish and Wildlife Service Partners for Fish and Wildlife Biologist, Maine Field Office

Among the bees and butterflies of early summer, you may see another character visiting flowers. Hover flies, also known as flower flies or syrphids, are common sights in Maine, but unless you know what you’re looking for, you might not actually see them. These small flies are often confused with wasps and bees due to their coloration and flower-visiting behavior. Although hover flies share some characteristics with these other insects, their unique traits make them a welcome resident in any garden.

Hover Fly Identification

Observing a hover fly at rest, lets you see a key identifying feature. Hover flies are a member of the order Diptera (the fly order), which comes from the Greek word meaning “two-winged.” All flies, including hover flies, have only two wings, whereas bees and wasps have four wings. Hover flies have much larger eyes than bees and wasps and stubby, short antennae. Adult hover flies are typically color mimics of wasps and bees, sporting yellow and black stripes. This coloration is a form of protection from predators who confuse hover flies for their stinging counterparts. Unlike wasps and bees, however, hover flies do not sting. While more difficult to spot, hover fly larvae can be found on plant leaves and stems; they look like caterpillars but have a tapered shape.

The Unsung Hero

While most of us know that lady beetles are good for controlling garden pests, each hover fly larva consumes hundreds of soft-bodied insects over their 1- to 3-week larval phase. Adult hover fly females lay eggs close to pest populations so their young can begin to feed on things like aphids and thrips immediately after hatching. Adult hover flies are also underappreciated. Mature hover flies feed on nectar and pollen, making them excellent pollinators. While they are not as efficient as bees, hover flies can travel quite far and spread the pollen on their bodies to new populations of plants, facilitating genetic information exchange.

Supporting Hover Flies

Between their pest control and pollination services, hover flies are an asset to a property. A great first step to support hover flies is to reduce or eliminate insecticide use, especially around flowering plants. Insecticides are a triple whammy for hover flies as they harm both adult and larval hover flies and also reduce the food source (insect pests) of the larvae. If you’re interested in the pest control and pollination benefits of hover flies, you’ll need to do three things:

1. tolerate a low level of insect pests as a food source for hover fly larvae,
2. provide a continuous supply of flowering plants as pollen and nectar sources for adult hover flies (hover flies tend to visit small white or yellow flowers like mustards, carrots, and asters, or herbs that you let flower), and
3. don’t remove your leaf litter over the winter to help hover flies overwinter safely.

This summer, take a moment to really study those black and yellow insects humming around your property. Among the bees, you’ll be able to pick out our small, but mighty, hero hover flies.

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Pollinator Ponderings: Let’s Talk Pollinator-Friendly Annuals

By Susan Joakim, York County Master Gardener Volunteer

Creating a pollinator-friendly garden means choosing plants that support a wide variety of pollinators as well as providing food for the entire season. While perennials—plants that live for more than two seasons—are often the foundation of such gardens, annuals and tender perennials (plants that are perennials in warmer climates, but don’t survive our winters) also play an important role. These short-lived companions also help keep the pollinator pantry well-stocked from spring through fall.

Whether you purchase plants from local garden centers, start them from seed indoors, or sow them directly in the garden, selecting a variety of colors, sizes, flower shapes, and heights is key to supporting a diverse range of pollinators. Grouping plants in clusters of three or more not only creates a stronger visual impact, but also makes it easier for pollinators to locate and access the blooms.

Keep in mind that some varieties of popular annuals have been bred for specific traits and, in the process, have lost their ability to produce pollen. Be sure to look at descriptions on plant labels and seed packets for whether the variety you’re considering is pollinator-friendly or, conversely, a low-pollen producer.

Here is a short list of trusty annuals you can choose from to provide a full season of food for pollinators, as well as beauty for your garden.

Ageratum spp.	Floss flower
Antirrhinum majus	Snapdragon
Calendula officinalis	Calendula
Cleome hassleriana	Spider flower
Cosmos bipinnatus	Cosmos
Fuchsia x hybrida	Fuchsia
Gaillardia spp.	Blanketflower
Gladiolus x hortulanus	Gladiolus
Helianthus annuus	Sunflower
Ipomoea purpurea	Morning glory
Lantana	Lantana
Lobularia maritima	Sweet alyssum
Nicotiana alata	Flowering tobacco
Pentas spp.	Pentas
Petunia x hybrida	Petunia
Phaseolus coccineus	Scarlet runner bean
Salvia elegans	Pineapple sage
Tagetes patula	Marigold
Tithonia rotundifolia	Mexican sunflower
Tropaeolum majus	Nasturtium
Verbena spp.	Verbena
Zinnia elegans	Zinnia

 

 

 

It should be noted that many annual herbs attract pollinators as well. For example, planting dill or fennel in your garden will attract the Eastern tiger swallowtail. Consider adding these to your vegetable garden, as a border, or plant among your perennials.

Anethum graveolens	Dill
Coriandrum sativum	Cilantro/Coriander
Ocimum basilicum	Basil
Origanum majorana	Marjoram
Salvia rosmarinus	Rosemary

 

 

 

 

 

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Chelsea Chop for Native Plants

By Lynne Holland, Horticulture Professional

The first of June is the start of the Maine summer, but across the “pond” in England, the first big event of the summer season, the Chelsea Garden Show, has already ended. This premier event of the season has dozens of gardens on display at their peak. Every plant is flawless, every flower is in bloom, and each space looks as if it belongs in a seed catalog photo. You might ask, “What does that have to do with native plants?”  This time of the year is also when English gardeners cut back their summer-blooming perennials to direct and control the parade of blooms in their gardens. Cutting them back now slows their growth, limits the ultimate height, and promotes branching and side shoots.

This is a perfect strategy for native plants, as one barrier for their use, especially straight species, is that they tend to be taller and less “tidy” than their cultivated counterparts. Their wilder growth habits can be a problem, especially in smaller urban gardens, narrow borders, or places where homeowner association restrictions apply. For example, the spirit is willing to put in that Joe-Pye weed (Eupatorium purpureum), but the garden is not able to handle its 7-foot height. Another situation the Chelsea chop may address is a mass planting of giant goldenrod (Solidago gigantea), which creates a great view from above, but the scene at 12 to 18 inches is pretty bleak, and it tends to flop down in late summer thunderstorms.

In its purest form, the Chelsea chop (not for the faint of heart) is cutting one-third to one-half of the growth of a flowering plant about 4–6 weeks before it would normally bloom. This cut is straight across and done in late spring or very early summer. That’s right, take a plant that is looking healthy, full and green and just CHOP it in half.

In Maine, for most plants, ideal timing is very late May or early June, though some late-blooming plants can be cut back into early July. When the plant is cut back, it will delay the blooming, but it will promote the growth of side shoots. The overall height of the plant at blooming will be shorter. Some plants that respond well to this basic version of the Chelsea chop are in the table below.

Genus	Common Name	Genus	Common Name
Agastache	Hyssop	Solidago	Goldenrod
Coreopsis	Tickseed	Verbena	Vervain
Eutrochium	Joe Pye Weed	Veronica	Ironweed
Helenium	Sneezeweed	Mondarda	Wild bergamot
Pycnathemum	Mountain Mint

A cascading Chelsea chop is when the cut of the plant is half in the front or around the perimeter and a third in the back (or center) to create a layered plant. The plant will get bushier and be more mounded-looking. This look is not for every plant since air circulation is critical around some plants to prevent disease.

If you have the nerve to live on the wild side, you can do the Chelsea chop in a stagger cut as well. This can result in a slightly staggered bloom time. For this to be successful, the plant or group of plants needs to be large and established. Do the cutting in sections. One section or set of sections is done in late May. Then, a second section is done two weeks later in mid-June. If you have a long growing season or a late-blooming plant (at least 8 more weeks until frost), then do another section in late June. Plants that do well with this technique are in the table below.

Botanical Name	Common Name	Botanical Name	Common Name
Agastache	Hyssop	Solidago	Goldenrod
Coreopsis	Tickseed	Symphyotrichum, Boltonia, Eurybia spp.	Aster
Helenium	Sneezeweed	Phlox paniculata	Phlox

Most gardeners are familiar with deadheading. The last version of the Chelsea chop is deadheading on steroids. Immediately after blooming, shear the plant in half. These are usually spring-blooming perennials, and the shearing is done early or midsummer. This forces the plant to put its energy into new growth rather than seed production. For some plants, this may include a second bloom later in the summer or fall. It also means removing the seed heads and going into the fall with refreshed foliage. Some plants that respond well to this technique are listed below. If you have an aggressive self-seeder (yarrow, anyone?), this also helps slow that down as well.

Genus	Common Name	Genus	Common Name
Achillea	Yarrow	Phlox	Creeping phlox
Aquilegia	Columbine	Polemonium	Jacob’s ladder
Carex	Sedge	Thalictrum	Meadow Rue
Penstemn	Beardstongue	Tradescantia	Spiderworts

The Chelsea chop is all about timing and knowing the natural inclination of the plant.  Generally, the Chelsea chop is done between Mother’s Day and Father’s Day. There are four ways to do it and a multitude of combinations of those four, depending on the herbaceous perennials in the garden, to create the effect you are looking for. Native plants are especially suited to this strategy because you use their natural reactions to the pruning to direct growth. It could be said that the Chelsea chop tames and cultivates the native plant without changing its genetic structure or future generations.

Resources
Izel Plants Blog: Taming the Wild

My Home Park Blog (includes short video): The Chelsea Chop: How and Why You Should Use this Technique | My Home Park – Curated Native Gardens Delivered to Your Door

Grow It Build It Blog: The Chelsea Chop – What Is It, How & When To Do It – GrowIt BuildIT

Bright Lane Gardens Blog and Video: How To Do The Chelsea Chop: Complete Guide And Video – Bright Lane Gardens

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Invasive Plant Educational Workshops

Presented by: University of Maine Cooperative Extension, NRCS, MNAP, and Maine Forest Service

Join us for a full day of learning and field exploration! These Invasive Plant Educational Workshops are designed to equip landowners, land managers, foresters, and natural resource professionals with the knowledge and tools to address invasive plant species in Maine.

Workshops will cover:

• invasive plant biology and ecology
• identification skills
• ecological impacts
• management principles
• overview of related state and federal programs

Each session includes classroom instruction and hands-on fieldwork. Get ready for an action-packed and informative day!

Workshop Locations and Dates

Piscataquis County
Date: Tuesday, July 22, 2025
Time: 10:00 a.m. – 4:00 p.m.
Location: Congregational Church, 824 West Main St, Dover-Foxcroft, ME 04426
Registration Deadline: July 15, 2025

Aroostook County
Date: Tuesday, August 5, 2025
Time: 10:00 a.m. – 4:00 p.m.
Location: Houlton High School, 7 Bird Street, Houlton, ME 04730
Registration Deadline: July 29, 2025

York County (Maple Producers Focus)
Date: Tuesday, September 9, 2025
Time: 10:00 a.m. – 4:00 p.m.
Location: Andy’s Agway/Cole Farm Maple, 13 Cole Farm Road, Dayton, ME 04005
Registration Deadline: September 2, 2025

Cost & Registration

Fee: $30
Includes

• Invasive Plants Field Guide
• Lunch

Register Online
 Space is limited to 20 participants per session. Registration is required.

Note: Outdoor identification sessions will be held rain or shine. Please dress appropriately.

Contact

Nick Rowley
Phone: 207.778.4650
Email: nicholas.rowley@maine.edu

For questions, dietary accommodations, or information about future workshops, please reach out.

Accessibility
To request a reasonable accommodation, contact Nick Rowley using the details above.

We strive to make this course accessible and affordable. If the registration fee is a barrier to participation, please contact us.

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At-Home Courses for Maine Gardeners Backyard

Ready to grow your gardening knowledge and make a real impact? Whether you’re looking to support pollinators, grow food, or pursue in-depth horticulture training, UMaine Cooperative Extension offers flexible, expert-led courses to help you reach your goals. Explore our Pollinator-Friendly Gardening course today—and mark your calendar for our fall horticulture training opportunities!

Pollinator-Friendly Gardening Course

If you’re looking to make pollinators a priority in your garden this summer, our Pollinator-Friendly Gardening course is a great way to get started. Designed for beginners, this online course will guide you through the basics of creating and maintaining a garden that supports a variety of pollinators.

You’ll have the flexibility to learn at your own pace as you explore how to design pollinator  habitat that offers food, water, shelter, and protection. This course is perfect for anyone interested in certifying their garden as pollinator friendly or simply looking to help support their local ecosystem.

Checkout the course website to learn more and register today.

Save the Date for In-Depth Horticulture Training

UMaine Cooperative Extension will offer three in-depth online horticulture trainings, tailored to your needs, from October 2025 to March 2026:

• Master Gardener Volunteer Training Applications will be available on July 21, 2025, at noon and due August 15, 2025, at 4:30. Open to all Maine counties, space may be limited in some counties and volunteer opportunities may be limited to specific projects. More details will be available on our website in July. Accepted applicants will receive registration details in September.
• Maine Gardener Training The same comprehensive curriculum, without the volunteer commitment.
• Maine Horticulture Apprentice Training In-depth training plus a micro-credential to help launch your horticulture career.

Registration for the Maine Gardener and Maine Horticulture Apprentice trainings opens in late September. Spots are limited and filled on a first-come, first-served basis. More details are coming in Maine Home Garden News this summer.

Bite-Sized Gardening: Learn the Basics in Minutes

New to vegetable gardening or looking to improve? Check out our Victory Garden for ME video series. These 10 free videos (10–20 minutes each) cover the essentials of planning, planting, and caring for your first garden; perfect for beginners and busy schedules.

Looking to dive deeper into a specific topic? Check out our webinars on demand. Here’s just a taste of some of the topics:

• Seed Starting at Home
• Growing Great Tomatoes, Peppers, Melons and More
• Preparing Your Garden Site: Getting Ahead of Weeds
• Mushroom Cultivation
• Backyard Composting
• Science of Pruning
• And lots more!

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Bird of the Month: Eastern Phoebe

By Maine Audubon Field Naturalist Stacia Brezinski

“FEE-BEE!!” Many Mainers look forward to this raspy song each spring. Eastern Phoebes spend the winter in the southern United States and Mexico and are

early migrants back to the Northeast. These large flycatchers are dark gray with nearly black heads and light undersides that often show a faint yellow wash. Their large eyes—typical of flycatchers—help them find flying insects, which they snatch on the wing in open spaces like meadows and lawns. The sky is a phoebe’s buffet, but they also glean ticks, making them handy neighbors for mammals like us. Spot phoebes on a branch, fence, or wire, pumping their long tails and scanning for food. While many birds wag their tails in the presence of a predator (“I see you! Don’t waste your time!”), the phoebes’ constant pumping is thought to be a clever “just in case” tactic, sending a message to anyone who might be watching. Their memorable songs vary among individuals, and while these differences are subtle, they allow birds to identify each other. Eastern Phoebes can be distinguished from similarly colored Dark-eyed Juncos by their small black beaks, long tails, and perches a few feet up or higher (juncos forage on the ground). Phoebes nest on sheltered ledges, including cliffs, bridges, barns, and houses. If you find an Eastern Phoebe nest with an odd speckled egg thrown in, that may be the work of a Brown-headed Cowbird. They are brood parasites that lay eggs in the nests of other species. While humans may feel an urge to protect the phoebes when this happens, it’s important to note that Brown-headed Cowbirds are native and protected under the Migratory Bird Treaty Act, which prevents harm to birds and destruction of eggs or nests. Thankfully, Eastern Phoebes typically lay a second clutch in the same nest one to two weeks after the first chicks fledge. Their breeding season in the Northeast is from late April until early July.

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Maine Weather and Climate Overview

By Sean Birkel, Assistant Extension Professor, Maine State Climatologist, Climate Change Institute, Cooperative Extension University of Maine

NOAA statewide summaries, released since the last newsletter, rank April 2025 as 31st warmest (top 1/3) and 27th wettest (top 1/3) for data beginning 1895. Daily station observations from Bangor, Caribou, and Portland show that mean temperature for May (through the 28th) was near the historical normal, while precipitation was much wetter than normal at all three sites (Bangor, Caribou top 1/3; Portland top 1/6).  Indeed, Maine has seen frequent low to moderate rainfall since late March, and Mainers have noticed that rainfall occurred nine consecutive weekends.  Hydrologic indicators are therefore showing near or above normal for this time of year across most of the state, with the exception of some groundwater monitors still registering abnormal dryness as carryover from last fall’s drought.

The latest 10-day weather forecast (evening May 28) shows another weekend rainstorm and cool temperatures statewide, followed by a drier weather pattern with moderate to above normal temperature for most of the week.  The probabilistic climate outlook for the month of June (see table below) shows equal chances of above or below normal temperature and above normal precipitation.  The June–August summer outlook predicts above normal temperature and equal chances of above or below normal precipitation.  As always, visit weather.gov for the latest weather forecast for your area. For additional information, including historical temperature and precipitation data and weather forecast maps, visit the Maine Climate Office website