Butterfly Weed

Asclepias tuberosa
Other Common Name
Butterflyweed; Butterfly Milkweed; Pleurisy Root

Apocynaceae (dogbanes); formerly Asclepiadaceae (milkweeds)


Butterfly weed is an herbaceous perennial, often bushy with several stems arising from the base. Flowers massively displayed in terminal umbels (umbrella-like clusters with stalks all arising from the tip of the stem). Flowers in many shades of orange to brick-red, occasionally yellow. Blooms May-September. Leaves hairy, narrow, lance-shaped, dark green, on very short stems; unlike most other milkweeds, the sap of this species is not milky. Fruit long seedpods to 4½ inches long with numerous, tightly packed seeds in spirals, released and windborne on their silky floss.


Height: to 3 feet.


Photo of butterfly weed flowers
Butterfly Weed (Flowers)

Monarch butterfly 3.jpg

Monarch butterfly feeding on a bright yellow butterfly weed flower
Monarch butterfly on a butterfly weed at Young Conservation Area
Habitat and conservation

Occurs in upland fields, prairies, glades, roadsides, wasteland, dry and rocky woods, edges of woods, often on disturbed soil. There are nearly 20 species in the genus Asclepias in our state.

image of Butterfly Weed Distribution Map
Distribution in Missouri



New evidence based on molecular studies has persuaded botanists that all the milkweeds, which used to have their own family, should be grouped within the dogbane family, the Apocynaceae. A more conservative approach would keep them in the traditional milkweed family, the Asclepiadaceae. Thus books and other references will differ.

Human connections

Another common name, "pleurisy root," comes from this plant's historic use as a remedy for lung inflammation. There were many other medicinal uses made of this plant, which induces vomiting. Today, it is valued as a gorgeous native garden plant.

Ecosystem connections

In case the name doesn't make it clear, this milkweed is a favorite nectar plant for many butterflies, and the leaves are eaten by the caterpillars of monarch butterflies.