Original article by David Graper, former SDSU Extension Horticulture Specialist and Master Gardener Program Coordinator. Revised by Grace Villmow, graduate student in Natural Resource Management, under the direction and review of Lora Perkins, Associate Professor in Natural Resource Management, Kristine Lang and Amanda Bachmann.
Are you looking to add native plants to your home garden this season? Consider expanding your garden palette with milkweed species that are native to South Dakota. Milkweed blooms will fill your garden with bright orange, pink and white blooms from summer through fall with the added benefit of attracting and nurturing an abundance of pollinators! Look for these four unique milkweeds in native plant catalogs and at your local garden center.
Butterfly Weed (Asclepias tuberosa)
Height: One to two-and-a-half feet
Bloom color: Orange
Bloom time: June to September (sometimes blooms twice!)
Conditions: Full sun to part shade, medium to dry soil
Butterfly weed (Asclepias tuberosa) was the 2017 Perennial Plant of the Year, a plant that is certainly deserving of this honor for its long-lasting, bright orange blooms. Butterfly weed is attractive to gardeners for its shorter stature than many other milkweeds. Although it may take a year to fully establish itself, butterfly weed blooms from June to September in the Great Plains and is a slow spreader. Gardeners also love butterfly weed for its compact, bushy appearance, which makes this species of milkweed a stand-out in any sunny yard.
Swamp Milkweed (Asclepias incarnata)
Height: Two to five feet
Bloom color: Pink to violet
Bloom time: July - September
Conditions: Full sun to part shade, medium-wet to medium-dry soil
Swamp milkweed (Asclepias incarnata) is native to the Great Plains and is an excellent addition to your home garden. Don’t let the ‘swamp’ part of the name discourage you from trying this plant; you do not need a swamp to grow it! Although it prefers average moisture conditions, it can tolerate periods of dry weather, as well as some occasional standing water. If you have a lower spot in your yard that stays wetter, swamp milkweed is a great way to fill it. Swamp milkweed does not bush out as much as butterfly weed does. Its flowers are produced mid-summer to fall at the very top of its upright stems. All sorts of butterflies and bees will flock to the flowers, and Monarchs will readily use this plant as a food source for their larva.
Common Milkweed (Asclepias syriaca)
Height: Three to five feet
Bloom color: Pink
Bloom time: July - September
Conditions: Full sun to part shade, medium to dry soil
Common milkweed (Asclepias syriaca) was once an abundant plant found in road ditches, fence rows and Conservation Reserve Program (CRP ) land across the Great Plains, but reductions in CRP acreage, as well as the removal of fence rows has dramatically reduced its numbers. Like butterfly weed and swamp milkweed, common milkweed can be utilized in the garden. However, gardeners need to keep an eye on it, since it spreads by rhizomes that will allow the plant to spread quite rapidly in the garden, given the chance. Common milkweed has a much coarser texture than the other two milkweeds, with leaves that are about four to five inches long and about two to three inches wide. The stems are also quite large, allowing the plant to grow taller than other species. The rounded umbels of pink flowers begin to develop in mid-summer and will continue up until frost. Of the milkweeds listed here, common milkweed would best be used in a more-naturalized setting that has a bit more of a wild look. Common milkweed can produce a lot of seed in the fall.
Whorled Milkweed (Asclepias verticillata)
Height: One to two feet
Bloom color: White
Bloom time: July - September
Conditions: Full sun to part shade, medium to dry soil
Whorled milkweed (Asclepias verticillata) is known for its fine, needle-like leaves and delicate, white flowers. Like butterfly weed, whorled milkweed is a shorter plant which may be preferred in small gardens. Less like butterfly weed and more like swamp milkweed, whorled milkweed tends to grow in individual stalks versus a clump. It flowers from July to September in the Great Plains, and both its flowers and seed pods are prized in floral arrangements for their delicate, spindly appearance. Whorled milkweed gets its name from its leaves, which appear to grow from its stem in whorls, or spirals. For a greater variety of color, you might try pairing whorled milkweed with plains milkweed (Asclepias pumila), which has a similar structure and pink flowers.
Milkweed Seed Production and Management
In the fall, Milkweed seed pods are quite attractive, as they expose their seeds and the fluffy attachments that allow the seed to be carried a great distance. Deadheading, the removal of these seed pods, is recommended to keep milkweed plants from spreading seed around the garden. However, if you have extra room in your garden, and want the space filled naturally, don’t be afraid to leave a few seed heads on each plant. If you end up with too many seedlings next spring, just pull out the ones you do not want, or, better yet, dig them up and share them with a friend.
For more native plant resources be sure to visit the South Dakota Native Plant Initiative website.
