13 Irresistible Boston, MA Milkweeds (Asclepias spp.) to Grow for Butterflies

Clasping Milkweed likes places that are sunny, with a sandy and/or gravelly substrate. The distinct, broad leaves, of clasping milkweed which clasp the stem give it a rather bold architectural presence.

For companion plants, we should look to species that appreciate similar xeric conditions and won’t crowd its unique form. Consider mixing the planting with New England Blazing Star (Liatris scariosa var. novae-angliae), which blooms from August to September and provides nectar for visiting butterflies. Narrowleaf Mountain Mint (Pycnanthemum tenuifolium), which provides a needle texture to the garden and nectar for short-tongues bees. Yellow wild indigo (Baptisia tinctoria) provides yellow, pea-like blossoms in the spring and nitrogen to the soil. Gray goldenrod (Solidago nemoralis) blooms from September to October and provides late season nectar to native bees and butterflies. Little Bluestem (Schizachyrium scoparium) provide pupation areas and turns a copper-orange color in the fall.

Poke milkweed presents a slightly different challenge and opportunity as compared to other milkweeds. Unlike its sun-loving cousins, Asclepias exaltata typically prefers the dappled light and richer, moister soils of woodland edges or clearings. So, if you have such a spot your Boston, MA property, perhaps with a bit more loam or humus, it could thrive. Its tall stature and drooping umbels of greenish-white to pale pink flowers are quite distinct.

Suitable companion plants would be those that share this affinity for partial shade and mesic conditions. Think about plants like golden alexanders (Zizia aurea) to provide early spring color, a landing place for short-tongued bees, and a host plant for black swallowtails (Papilo polyxenes). Great blue lobelia (Lobelia siphilitica) that blooms from August to October and provides nectar for native bumblebees. Black Cohosh (Actaea racemosa) to give height to the garden, attract solitary bees, and a food source for the Appalachian Azure butterfly (Celastrina neglectamajor). Blue Wood Aster (Symphyotrichum cordifolium) to provide a late source of nectar from September to November. Finally, you could add northern sea oats (Chasmanthium latifolium) to give a place for pupa formation. Just be careful this species does get out of control in the garden.

Swamp milkweed, as its name would suggest, is a lover of moisture. Whether it’s a sunny streamside, a moist meadow, or a rain garden, Asclepias incarnata is in its element. In Boston, if you have areas with consistently damp soil this plant can thrive. Its vibrant pink to mauve flowers are a magnet for a wide array of pollinators.

So, what companions appreciate similar conditions? Cardinal Flower (Lobelia cardinalis) would provide a stunning color contrast with its brilliant red flowers, also thrives in moist soils and attracts hummingbirds and bumblebees. Common boneset (Eupatorium perfoliatum) has white flowers that attract sweat bees, hoverflies, and most importantly, parasitoid wasps that can protect the milkweeds from aphids. Turtlehead (Chelone glabra) produces a unique hood shaped flower and is a host for the Baltimore checkspot butterfly (Euphydrayas phaeton). Golden alexander (Zizia aurea) for a splash of yellow in the early spring.

For plants that offer a different structure, consider Blue Flag Iris (Iris versicolor) or perhaps some of the moisture-loving sedges like Carex lurida or Carex crinita. Whatever plants are selected, make sure you select an area that is consistently moist.

Few-flower milkweed (Asclepias lanceolata), is often found in coastal plain habitats, savannas, and the edges of marshes. It certainly has potential for a Boston garden, particularly if you can offer it a spot with moist to wet, sandy, acidic soils and plenty of sun. Its slender form and striking reddish-orange flowers are quite captivating.

Given its preference for somewhat open, sunny, and moist conditions, consider pairing it with other coastal plain natives. Companion plants would be essentially the same as those for swamp milkweed above.

Purple milkweed (Asclepias purpurascens), with its rich, deep magenta flowers, is a truly stunning plant. It generally prefers sites with full sun to light shade and well-drained to medium-moist soils, often found in prairies, open woods, and glades. It can be a bit more particular than some other milkweeds. In Boston, MA, a spot with good drainage but some moisture retention would be key.

For companions, you might consider plants like clustered mountain mint (Pycnanthemum muticum), which feeds pollinators in the mid to late summer. Foxglove beardtongue (Penstemon digitalis), for long-tongued bees. Smooth Blue Aster (Symphyotrichum laeve), for late season color and a nectar source for native bees and migrating monarchs. Blue-stemmed goldenrod (Solidago caesia) to compliment the aster and provide pollen for oligoegethic bees. Finally, you can add bottle brush grass (Elymus hystrix) for pupation infrastructure and a unique texture. When planting this milkweed be sure your intended site offers a balance between sufficient moisture and good drainage that A. purpurascens appreciates.

This charming, smaller milkweed, four-leaf milkweed (Asclepias quadrifolia), is typically an inhabitant of dry to mesic upland woods, rocky slopes, and clearings, often in part shade. Its delicate pinkish-white flowers appear relatively early for a milkweed. So, in the Boston area, we’d be looking for a location that mimics these conditions.

What would thrive alongside it? Consider Wild Columbine (Aquilegia canadensis), which shares a love for well-drained soils and partial shade, and has early blooms for hummingbirds and queen bumblebees. Wild geranium (Geranium maculatum), which has a pink to lavender flower that provides nectar for short-tongued bees and hoverflies. Blue-stemmed goldenrod (Solidago caesia) that provides a mid to late season yellow color and nectar to native bees. White wood aster (Eurybia divaricata), which provides early season white flowers and a place for smaller butterflies to perch. Pennsylvania sedge (Carex pensylvanica) that provides pupation structure.

Asclepias rubra, or Red Milkweed, is an interesting milkweed. It typically inhabits bogs, pocosin edges, and moist pine savannas, primarily in the coastal plain of the southeastern U.S. In the Boston, MA area, this species would require a dedicated spot with consistently moist to wet, acidic, sandy or peaty soil, and full to partial sun.

Are you cultivating such specific conditions? If so, its companions would be other acid-loving, moisture-tolerant plants. This could include Virginia meadow beauty (Rhexia virginica), which attract native bumblebees. Bog goldenrod (Solidago uliginosa) that provides late season nectar for butterflies and bees in wetlands. Pink tickseed (Coreopsis rosea) that provides nectar to short-tongued bees and small skipper butterflies. Slender blue flag (Iris prismatica), a nectar plant for long-tongued bees. Finally, rough wood aster (Eurybia radula), a plant that continues to provide nectar after the milkweed has gone to fruit.

Asclepias speciosa, or Showy Milkweed, is a magnificent plant that is often a featured plant in butterfly gardens in the US. From an ecological perspective, it’s primarily a species of the western and central United States, thriving in prairies and open areas. In Boston, MA it is best considered a plant for container gardens due to it being far from its native range. However, it can also be planted in open gardens.

Suitable companion plants to showy milkweed include clustered mountain mint (Pycnanthemum muticum) that provides nectar to most garden visitors. Wild bergamot (Monarda fistulosa), a mid to late summer flowering plant that provides nectar for bumblebees and sphinx moths. New England Aster (Symphyotrichum novae-angliae), a late season bloomer and nectar source. Blazing star (Liatris spicata), a late summer nectar powerhouse. Indiangrass (Sorghastrum nutans), a grass that provides pupa infrastructure and fall color.

When people think of milkweed, it is often the ubiquitous and invaluable Common Milkweed. Common milkweed is a standard for pollinators and a critical host plant for Monarchs. It’s adaptable, thriving in full sun and a range of soil types, from sandy loams to clay, though it does prefer well-drained conditions. It can be quite vigorous, so we must ask: are we prepared for its potential to spread?

For companions in the Boston area, think of other resilient, sun-loving perennials. This include those listed for showy milkweed above with the addition of switchgrass (Panicum virgatum). The key is to plant the milkweed where its spreading nature is an asset or where it can be managed such as large field.

Butterfly Weed (Asclepias tuberosa) is a truly spectacular plant with its brilliant orange (sometimes yellow) flowers, and it’s a fantastic choice for Nantucket’s sun-baked, sandy, and well-drained soils. It’s quite drought-tolerant once established. What companions would suit this sun-lover? Consider pairing it with Lance-leaved Coreopsis (Coreopsis lanceolata) for a cheerful yellow-orange combination.

Other companions can include New England blazing star (Liatris scariosa var. novae-angliae), a plant that provides late season nectar. Narrowleaf mountain mint (Pycnanthemum tenuifolium), a plant that provides habitat for parasitoid wasps to keep aphids in check. Yellow wild indigo (Baptisia tinctoria), a yellow-flowering species in the spring, that can provide nitrogen for the garden and is a host plant Ensuring excellent drainage is paramount for A. tuberosa.

Asclepias variegata, sometimes known as White Milkweed or Variegated Milkweed, is quite handsome with its white flowers and is often tinged with purplish rings. This milkweed typically prefers dry to mesic soils in open woods, woodland borders, or clearings, often in part shade but can tolerate more sun if moisture is adequate. On Nantucket, a spot with well-drained soil and some protection from the most intense afternoon sun might be ideal.

Good companions in the Boston, MA area could include clustered mountain mint (Pycnanthemum muticum), to attract beneficial wasps to guard against aphids. Hairy beardtongue (Penstemon hirsutus), to have lavender flowers and long-tongued bees. Wild columbine (Aquilegia canadensis), to attract hummingbirds. Blue wood aster (Symphyotrichum cordifolium), for an late season nectar source for migrating monarchs and other insects. Finally, for some texture, bottlebrush grass (Elymus hystrix) is a good addition. Generally, you want to aim for a woodland edge habitat.

Whorled Milkweed (Asclepias verticillata) is a delightful, fine-textured plant that thrives in full sun and dry to medium, well-drained soils, often in prairies, glades, and open disturbed areas. Its slender profile and greenish-white flowers are attractive to a wide range of smaller pollinators.

Given its preference for leaner conditions, it would pair wonderfully with some of the smaller native grasses like Poverty Oat Grass (Danthonia spicata) or Purple Lovegrass (Eragrostis spectabilis), which adds late-season color. Aromatic Aster (Symphyotrichum oblongifolium) could provide late-season nectar and thrives in similar sunny, drier spots. For a very low companion, perhaps Field Pussytoes (Antennaria neglecta). The fine texture of A. verticillata provides a wonderful contrast to broader-leaved plants.

Also known as Green milkweed, Asclepias viridiflora is typically found in prairies, glades, and open woodlands, preferring full sun and dry to mesic, often calcareous soils, though it can tolerate sandy and gravelly sites as well. Its greenish, uniquely shaped flowers are quite intriguing. In the Boston, MA area, finding a spot with full sun and excellent drainage would be crucial.

Good companions would be those that don’t mind these drier, leaner conditions. Consider Hoary Vervain (Verbena stricta), a tough plant with upright purple flower spikes. Spotted Bee Balm (Monarda punctata) is another excellent choice for sandy soils, attracting a fascinating array of wasps and bees. Little Bluestem (Schizachyrium scoparium) would again be an appropriate grass, reinforcing that prairie-like feel. The subtlety of its green flowers lends itself to being planted in places it where it can be appreciated up close.