A peony clump returning after a Maine winter is one of the quiet pleasures of a New England yard, and the plant is built for that kind of cold. Herbaceous peonies are the dependable choice here, with tree peonies and intersectional hybrids as worthwhile additions for gardeners who want a longer season of flowers.
Best Peonies to Grow in Maine
Maine is a natural peony state, because these plants need a real winter rest to flower and the state delivers one. Four types are generally grown in home landscapes: woodland, tree, herbaceous and intersectional. The hardiness range runs from zone 3b to 6a on the USDA system, so conditions differ across the state.
Garden Peony
The garden peony, also called the herbaceous peony, is a classic border plant and a dependable choice for a Maine yard. It needs a cold winter rest to flower, and Maine generally provides one.
It dies back every year, so cut the foliage down after frost, in November or December. Early spring in March or April works too.
Intersectional Peony
Also known as the Itoh, this is a hybrid of the garden and tree peonies. It carries the lush flowers of a tree peony on a plant that behaves much like a garden peony.
It comes last in the bloom sequence, so it stretches the show well into June. Its flowering follows the herbaceous types, making it a useful way to extend the season in a Maine bed.
Tree Peony
The woody tree peony, including Paeonia suffruticosa, keeps its stems through winter. That means it is never cut to the ground, so only remove dead wood.
Tree peonies flower ahead of the herbaceous types, making them an early part of the peony season.
Woodland Peony
The woodland peony, Paeonia japonica, is the white-flowered type that opens the season. It leads the sequence before the other types take over.
It is the one to consider for a shadier corner, and it gives the earliest peony flowers in a mixed planting.
Maine — the year and the numbers
- State
- Maine
- USDA zones
- 3b-6a
- Last spring frost
- April 22 to May 1
- First fall frost
- October 9 to October 21
- Annual rain
- 48 in
- Lawn zone
- cool-season
- Source
- NOAA NCEI 1991-2020 Climate Normals, 32F freeze probabilities · Portland
How to Choose a Peony for a Maine Garden
Start with what your yard asks of the plant. The herbaceous peony is a practical starting point, because winter cold is what sets its flowers.
Planting is best in August and September, and October also works. Spring planting is possible but may delay flowers a year.
| Your situation | What suits it in Maine | Why |
|---|---|---|
| Very cold winter | Garden peony | It dies back each year and needs winter cold to flower |
| Need for winter chill | Garden or intersectional peony | Flowering depends on a cold winter rest |
| Want woody winter structure | Tree peony | Its woody stems stay put, so there is no cutting back to the ground |
| Long season of bloom | A mix of woodland, tree, garden and intersectional | Their flowering overlaps from late spring into June |
A newly planted or transplanted peony may not bloom the first spring, so patience is part of any of these choices.
Which Peonies Suit Different Parts of Maine
Maine spans a wide range of winters, and the choice shifts a little with it.
- Portland and the southern coast: this is the milder end of the state, with the last spring frost falling between April 22 and May 1. Local conditions still matter when choosing among these types.
- Inland Maine: winters run colder and spring frost comes later, so the garden peony is the dependable anchor of the bed.
- Northern Maine: the cold is deepest here, and the hardy herbaceous peony is the surest bet. Tree peonies deserve more caution where the winter is hardest.
Wherever you garden, the winter chill peonies need is not in doubt.
Peony Buying Mistakes to Avoid in Maine
Planting Too Deep
A peony set too deep may bloom poorly or never come up. The result can be a plant that produces few or no flowers.
Keep the eyes near the soil surface when you plant in late summer or early fall.
Cutting a Tree Peony Back
Treating a tree peony like a garden peony removes the woody stems that carry next year’s flowers. Herbaceous types are cut back after frost, but a tree peony keeps its stems and is never cut to the ground.
Check the label before the pruners come out in November.
Expecting Flowers the First Year
A peony bought in a pot and planted this year may not bloom the first spring. Buyers who expect an instant show often assume the plant has failed.
Plant in August or September so the roots settle before winter, and let the plant establish at its own pace.
Where to Get Peony Advice in Maine
The University of Maine Cooperative Extension publishes guidance on peonies, including when to transplant them, and its offices answer local questions.
- Browse University of Maine Cooperative Extension for peony articles before planting season in late summer.
- Contact your county extension office with photos if a clump fails to flower in May or June.
Common Questions
Can You Plant a Peony in Spring in Maine?
Yes. Spring planting is possible, though it may delay flowers a year compared with planting in August or September.
When Do Peonies Bloom in Maine?
Peonies bloom from May into June, depending on the type.
When Should You Cut Back Peonies in Maine?
Cut herbaceous peonies back in November or December once the foliage has died back. March or April is the other window.