Milkweed in Maine
Maine sits at the northeastern edge of the monarch breeding range, where common milkweed colonizes old fields, blueberry barrens and roadsides. Coastal fog and a short season mean plants leaf out late but grow lush; swamp milkweed thrives along the state’s abundant wetland margins.
The best milkweed to plant in Maine
Native to the state, garden-worthy and useful to monarchs. Start here if you are planting rather than identifying.
All milkweed species in Maine
| Species | Height | Flower | Bloom | Soil | Monarch |
|---|---|---|---|---|---|
| Swamp Milkweed Asclepias incarnata |
3 ft–5 ft | pink, rose, white | June to September | Wet / Average | |
| Butterfly Weed Asclepias tuberosa |
1 ft–3 ft | orange, yellow, red | May to September | Dry / Average | |
| Purple Milkweed Asclepias purpurascens |
2 ft–4 ft | purple, magenta | May to July | Average / Dry | |
| Poke Milkweed Asclepias exaltata |
3 ft–6 ft | white, green | June to July | Average | |
| Common Milkweed Asclepias syriaca |
3 ft–6 ft | pink, mauve, white | June to August | Dry / Average |
Planting milkweed in Maine
Sow seed outdoors in late October to early December. Winter then supplies the cold-moist stratification most milkweed seed needs, and germination happens naturally as the soil warms. If you have missed that window, chill seed in the refrigerator for 30 days and sow after your last frost. The full method is here.
Maine spans USDA zones 3b–6a, so check the zone range on each species page before committing. Match the species to your site rather than the other way round: dry, sunny and poor suits butterfly weed and the whorled species; a damp spot suits swamp milkweed; shade suits very few milkweeds at all.
Plant at least ten stems in one group rather than scattering them, because female monarchs find dense patches far more readily. Add late-season nectar such as goldenrod and asters so the fall migratory generation has fuel as well as host plants. How to lay out a monarch garden.
Where to buy milkweed in Maine
Start with Wild Seed Project. State native plant societies run the plant sales worth going to: locally grown, untreated stock, at a few dollars a plant, sold by people who can tell you where to put it.
In Maine
Maine non-profit selling wild-type native seed and running sowing workshops.
Elsewhere in the northeast
Independent seed producer supplying restoration-scale native seed by the pound.
Small independent mail-order nursery for eastern natives.
Independent grower supplying Mid-Atlantic restoration work.
Independent Pennsylvania native plant and tree nursery.
Ships to you
One of the widest milkweed seed and bare-root ranges anywhere, with germination codes listed for every species.
Long-established independent nursery specializing in Midwestern natives.
Family-run native seed producer for the eastern and central states.
Family-run Texas seed house focused on regional ecotypes.
Independent nursery growing Missouri-provenance natives.
These favor independent nurseries and non-profits over chain garden centers, which mostly stock unlabeled tropical milkweed and often cannot tell you whether it has been treated with neonicotinoids. Search the full directory by ZIP code.
Milkweed in Maine: common questions
What milkweed is native to Maine?
5 milkweed species are recorded in Maine, including Swamp Milkweed (Asclepias incarnata), Butterfly Weed (Asclepias tuberosa), Purple Milkweed (Asclepias purpurascens), Poke Milkweed (Asclepias exaltata). The full list is on this page.
What is the best milkweed to plant in Maine?
Swamp Milkweed, Butterfly Weed, Purple Milkweed are the best combination of native, available and garden-worthy for Maine. Swamp Milkweed is the easiest to start with.
When should I plant milkweed seed in Maine?
Sow outdoors in late October to early December, so winter provides the cold stratification the seed needs. If you have missed that window, stratify seed in the refrigerator for 30 days and sow in spring after the last frost.
Does milkweed grow wild in Maine?
Yes. 5 species occur in Maine, typically on roadsides, field margins, prairie remnants and along watercourses. Maine sits at the northeastern edge of the monarch breeding range, where common milkweed colonizes old fields, blueberry barrens and roadsides.
Cite this page
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Milkweed USA. (2026). Milkweed in Maine. Retrieved DATE, from https://milkweedusa.com/states/maine/
"Milkweed in Maine." Milkweed USA, 2026, https://milkweedusa.com/states/maine/. Accessed DATE.
Milkweed USA. "Milkweed in Maine." Last modified 2026-08-01. Accessed DATE. https://milkweedusa.com/states/maine/.
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}