Butterfly Weed

Asclepias tuberosa

butterfly_weed_plant_12-31-13.jpg

Photo of butterfly weed plant with flowers
Butterfly weed, a type of milkweed, is a favorite nectar plant for butterflies, and the leaves are eaten by the caterpillars of monarchs. One of our showiest native wildflowers, butterfly weed is also a favorite of gardeners.
David Stonner
Other Common Name
Butterflyweed; Butterfly Milkweed; Pleurisy Root
Family

Apocynaceae (dogbanes); formerly Asclepiadaceae (milkweeds)

Description

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.

Similar species:  There are nearly 20 species in the genus Asclepias in our state. The flower shape of milkweeds is very distinctive. This is our only milkweed with orange flowers.

Size

Height: to 3 feet.

butterfly_weed_in_prairie_12-31-13.jpg

Photo of butterfly weed plant on a prairie
Butterfly Weed
Butterfly weed, striking for its pure orange color, occurs in upland fields, prairies, glades, roadsides, wasteland, dry and rocky woods, and edges of woods, often on disturbed soil.

butterfly_weed_flowers_12-31-13.jpg

Photo of butterfly weed flowers
Butterfly Weed (Flowers)
A close look at the individual flowers of butterfly weed shows they have the same unique structure as other milkweeds.

Butterfly_Weed_6-30-14.jpg

Butterfly weed flower clusters and leaves
Butterfly Weed Flower Clusters
The flowers of butterfly weed are massively displayed in umbrella-like clusters, with stalks all arising from the tip of the stem. They can be many shades of orange to brick red, and occasionally yellow.

Monarch butterfly 3.jpg

Monarch butterfly nectaring on a bright orange butterfly weed flowers
Monarch On Butterfly Weed at Young Conservation Area

Coral_Hairstreak_4-23-19.jpg

Coral hairstreak butterfly on butterfly weed flowers
Coral Hairstreak on Butterfly Weed Flowers
The coral hairstreak is the only Missouri hairstreak lacking hindwing “tails” and without a blue spot on the outer hindwing edge. It loves butterfly weed flowers.
Habitat and conservation

Occurs in upland fields, prairies, glades, roadsides, wasteland, dry and rocky woods, and edges of woods, often on disturbed soil.

image of Butterfly Weed Distribution Map
Distribution in Missouri

Statewide.

Status

New evidence based on molecular (DNA) studies has persuaded botanists that the milkweeds, which used to have their own family, should be grouped within the dogbane family, the Apocynaceae. Formerly, the milkweeds were placed in their own family, the Asclepiadaceae, but now they are considered a well-defined subdivision of the dogbane family. Be aware that 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 that is superb for attracting butterflies.

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.

While you’re admiring butterfly weed's orange flowers, keep an eye out for coral hairstreak butterflies. The single brood of this local and uncommon butterfly extends only from mid-June through July. The coral hairstreak has been described as being “addicted” to the blossoms of butterfly weed: “other flowers are practically ignored when this plant is present.”

Many other insects visit the flowers for nectar and chomp on the leaves, too, and their presence usually draws spiders, ambush and assassin bugs, robber flies, and other predators, forming a mini-ecosystem right on the plant. All of these invertebrates are on the menu for insect-eating birds.