South Dakota Native Plant Research
Asclepiadaceae : Asclepias verticillata

Asclepiadaceae : Asclepias verticillata


Download Seedlings (872 KB)

Download Plants in the garden (1.1 MB)

Download Flower buds (1.0 MB)

Family Name


Common Name

Whorled milkweed

Native American Name

Lakota: waȟpé thíŋpsila iyéčheča


Asclepias verticillata is a perennial herb containing milky white sap, with 1 to a few stems arising from a fibrous crown, occasionally branched and 35-90 cm tall. The sessile leaves are whorled with 3-6 leaves per node. The blades are entire, linear, 1.5 to 8 cm long and about 1 mm wide. The inflorescences are few to many in the axils of the upper leaves, each containing 6-20 flowers. Flower buds appear yellowish but produce white to greenish white flowers. Each flower is attached to a short peduncle (1-4 cm long) by a 5-11 mm pedicel. Calyx lobes are green to purple tinged 1-2.5 mm long and the corolla lobes are white to greenish white, reflexed and3.5-4.5 mm long. The fruit are erect follicles 8-10.5 cm long and < 1 cm wide. The ovate seeds are 5-6 mm long with long white hairs. Whorled milkweed blooms from June through September in the prairies, flood plains and open woods of South Dakota.

Additional Notes

Whorled milkweed can make an interesting addition to a garden. The flowers attract bumblebees and honeybees, and its leaves provide food for monarch butterfly caterpillars. This plant is toxic to livestock and is considered a weed in some areas.

Horticulture Notes

Seed Collection: Seeds turn brown and are released from the pods over an extended period. Unopened brownish pods that split when gently squeezed are the best source.

Germination: Seeds require 30 days of cold moist stratification before planting in the spring. Seeds planted in the fall will germinate in the following spring.

Vegetative propagation: Established plants can be divided in late spring and transplanted.

Light: Full sun to partial shade.

Soil: Sandy, clay or rocky soils.

Water: Medium to dry conditions.

Asclepiadaceae : Asclepias verticillata