List of Michigan Milkweeds
Michigan Milkweed Species to Include in your Butterfly Garden
There are twelve species of Michigan milkweeds (Asclepias spp.) that can be grown for Monarch Butterflies and other insects. Milkweeds are an important host species for Monarch, Queen, and Soldier Butterflies. The Monarch butterfly in particular uses the cardenolides found in the milky sap of milkweeds to give an unpleasant taste to predators. These plants are also an important nectar source to all insects visiting your pollinator garden. Michigan is divided into the lower and upper peninsulas by Lakes Michigan and Huron. For purposes of clarity, distributions are given using these peninsulas.
1. Clasping Milkweed (Asclepias amplexicaulis), a Michigan Milkweed for Dry Soils
Clasping Milkweed (Asclepias amplexicaulis): This Michigan milkweed is native to the western and south-central counties of the lower peninsula (Kartesz 2015). In the wild, clasping milkweed grows in dry woodlands, prairies, meadows, and roadsides that have sandy or gravelly soil. Growing up to 3 feet tall, this milkweed has greenish-pink, red-, brown, to purple flowers that bloom from March to Spetember.
In a garden setting, this milkweed is hardy in zones 3-9 and requires full sun to partial shade having dry sandy/rocky soil. Seeds for this species can be purchased in the McMullen House Bed & Breakfast Garden Shop.



2. Poke Milkweed (Asclepias exaltata), a Michigan Milkweed for Shade and Moist Soils
Poke Milkweed (Ascelpias exaltata): This Michigan milkweed is native in both the lower and upper peninsulas (Kartesz 2015). In the wild, poke milkweed grows in moist woods, roadsides, and edges of woods. Reaching a height of 2 to 6 feet, it is one of the taller milkweeds in Michigan and has flowers that are white to green with accents of rose, purple, or blue. The flowers bloom from May to August.
In a garden setting, this milkweed is hardy in zones 3-9 and requires part-shade to full shade in moist soil. For shade gardens, this is a choice milkweed. Seeds for this milkweed can be purchased in the McMullen House Bed & Breakfast Garden Shop.



3. Swamp Milkweed (Asclepias incarnata), a Michigan Milkweed for Moist Soils
Swamp Milkweed (Asclepias incarnata): This Michigan milkweed has two subspecies, ssp. incarnata and ssp. pulchra. The former is native throughout the state (hardy in zones 3-9), while the latter is native to one county in Michigan in the northeastern lower peninsula (Kartesz 2015). Like the name suggests this plant is found in wet places such as the shores of streams, lakes, ponds, and other wetlands. However, as a landscape plant it can exist in drier places. Growing from 3 to 5 feet tall, the flowers are variable and are generally a pink to red color, but there is also a white cultivar (pictured below).
In a garden setting, swamp milkweed requires full sun to part-shade and prefers moist to medium moisture soil, but can exist in drier soil. Seeds for this plant can be purchased in the McMullen House Bed & Breakfast Garden Shop.



4. Long-leaf Milkweed (Asclepias longifolia), a Michigan Milkweed for Moist Soils
Long-leaf Milkweed (Asclepias longifolia): This Michigan milkweed has two varieties, var. hirtella and var. longifolia. Of these var. hirtella is rare and occurs in scattered counties in the lower peninsula (Kartesz 2015). The other variety is not located in Michigan. In the wild, long-leaf milkweed grows in moist areas and wetlands such as bogs, swamps, flatwoods, and prairies having full sun. Reaching a height of 1 to 2.5 feet tall, the greenish-white flowers bloom from April to July.
In a garden setting, this milkweed is hardy in zones 4-9 and requires full sun and needs moist to wet soils.



5. Oval-leaf Milkweed (Asclepias ovalifolia)
Oval-leaf Milkweed (Asclepias ovalifolia): This Michigan milkweed is native and rare in one county (Menominee County) in the upper peninsula of state (Kartesz 2015). Oval-leaf milkweed grows in open areas having full sun or partial shade such as prairies, grasslands, savannas, railroad edges, and alluvial terraces. The white, pink, or green flowers bloom from May to August and the plant is hardy in zones 5-9. Seeds of oval-leaf milkweed can be purchased in the McMullen House Bed & Breakfast Garden Shop.



6. Purple Milkweed (Asclepias purpurascens)
Purple Milkweed (Asclepias purpurascens): This Michigan milkweed is native and rare in the south-central and central parts of the lower peninsula (Kartesz 2015). This plant grows in moist to dry places having full sun to part shade such as swamps, woodlands, meadows, roadsides, and dry fields. The purple to pink flowers bloom from May to July and it is hardy in zones 3-8. Seeds for purple milkweed can be purchased in the McMullen House Bed & Breakfast Garden Shop.



7. Showy Milkweed (Asclepias speciosa)
Showy Milkweed (Asclepias speciosa): This Michigan milkweed is adventive to one county (Mackinac County) in the upper peninsula (Kartesz 2015). Showy milkweed grows in open areas such as roadsides, fields, and woodlands that are mesic to dry. It has flowers that are purple to pink in color and bloom from April to June. This plant is hardy in zones 3-9. Seeds for showy milkweed can be purchased in the McMullen House Bed & Breakfast Garden Shop.



8. Sullivant’s Milkweed (Asclepias sullivantii)
Sullivant’s Milkweed (Asclepias sullivantii): This Michigan milkweed is native and rare in the southeast and eastern parts of the lower peninsula (Kartesz 2015). Sullivant’s milkweed grows in open areas with full sun such as prairies, meadows, roadsides, and railroads. In June and July the pink to purplish flowers come out and it is hardy in zones 3-7. Seeds of this plant can be purchased in the McMullen House Bed & Breakfast Garden Shop.



9. Common Milkweed (Asclepias syriaca)
Common Milkweed (Asclepias syriaca): This Michigan milkweed is native throughout the state on both peninsulas (Kartesz 2015) and is found in open areas such as fields, pastures, and roadsides, where it can receive full sun. The flowers range from pink, greenish-purple, greenish-white, to white and bloom from June to August. It is hardy in zones 3-9. Seeds of this plant can be purchased in the McMullen House Bed & Breakfast Garden Shop.



10. Butterfly Weed (Asclepias tuberosa)
Butterfly Weed (Asclepias tuberosa): This Michigan milkweed is one of the most common for butterfly gardeners on the east coast of the United States. Butterfly weed has three subspecies, two of which, subsp. interior and subsp. tuberosa occur in Michigan. Subspecies interior is located throughout the lower peninsula and one county in the upper peninsula. Subspecies tuberosa is located in one county (Kalamazoo County) in the lower peninsula. The flowers are characteristically orange and bloom throughout the summer and sometimes into the autumn. It grows in open areas with full sun such as fields, roadsides, and open woods and is hardy from zones 3-9. Seeds of butterfly weed can be purchased in the McMullen House Bed & Breakfast Garden Shop.



11. Whorled Milkweed (Asclepias verticillata)
Whorled Milkweed (Asclepias verticillata): This Michigan milkweed is native in scattered locations in the lower and upper peninsulas (Kartesz 2015). Whorled milkweed has green to white flowers that bloom from May to September. Like a lot of other milkweeds it grows in open areas such as meadows and fields, where it can take advantage of full sun. It is hardy in zones 3-9. Seeds for this plant can be purchased at the McMullen House Bed & Breakfast Garden Shop.



12. Green Comet Milkweed (Asclepias viridiflora)
Green Comet Milkweed (Asclepias viridiflora): This Michigan milkweed is native mostly to the south-central lower peninsula and scattered in the northwestern part of the lower peninsula (Kartesz 2015). The flowers, which bloom from June to August, begin as a green color but age to become yellow with a purple tinge. The habitat includes open areas such as meadows and field where there is full sun. It is hardy in zones 3-9. Seeds for green comet milkweed can be purchased at the McMullen House Bed & Breakfast Garden Shop.



When selecting your Michigan milkweed, be sure to make sure that it grows in your zone and habitat.
References for Michigan Milkweeds
- Kartesz, J.T. The Biota of North America Program (BONAP). 2015. Taxonomic Data Center. Link to website. Chapel Hill, N.C. [maps generated from Kartesz, J.T. 2015. Floristic Synthesis of North America, Version 1.0. Biota of North America Program (BONAP). (in press)]