Whorled milkweed in flower.

Whorled milkweed

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Pictured above: Whorled milkweed (Asclepias verticillata) by Emily Bell. Click on terms for botanical definitions. View post as a PDF.

Whorled milkweed (Asclepias verticillata) is one of the smaller, more delicate native milkweeds. It is found in pinelands throughout much of Florida. When not in bloom, it is easily overlooked. Its narrow leaves blend in with the grasses among which the plant typically grows. It flowers late spring through late summer and into early fall, attracting a variety of pollinators. Like all members of the Asclepias genus, Whorled milkweed is a larval host plant for Monarch, Queen and Soldier butterflies. The plant contains a milky latex that is toxic to most animals, but Monarch, Queen and Soldier caterpillars are adapted to feed on them despite the chemical defense. Learn more about Monarchs and Milkweed in Florida here.

Leaves are grasslike and arranged in whorls. Photo by Emily Bell
Flowers can vary slightly in color. Photo by Emily Bell

Flowers are born in pedicellate umbels in groups of 15–20. The corolla is reflexed and white to greenish-white with tips that may be tinged in reddish-purple. Pedicels are purplish. Leaves are long, linear and sessile. Margins may be entire or revolute. Leaves are arranged in whorls around the stem (hence the common name). Stems are thin and glabrous. Seeds are ovately flat with many fine, silky hairs (pappus) attached to their apices that aid in dispersal. They are born in smooth narrow follicles that split open as the fruit matures.

The genus Asclepias is named for Asclepius, the Greek god of healing, because some Asclepias species, such as A. tuberosa, are known to have medicinal properties. The species epithet verticillata refers to the verticillate (whorled) arrangement of the leaves.

Family: Apocynaceae (Dogbane family)
Native range: Nearly throughout
To see where natural populations of Whorled milkweed have been vouchered, visit www.florida.plantatlas.usf.edu/Plant.aspx?id=3470.
Lifespan: Perennial
Soil: Moderately moist to moderately dry, sandy to calcareous soils
Exposure: Full sun to minimal shade
Growth habit: 1–3’ tall
Propagation: Seeds
Florida regions of landscape suitability: North, Central, South
Garden tips: Whorled milkweed is suitable for a pollinator garden or wildflower meadow in moist to dry well-drained soil and flowers best in full sun. It can both reseed and spread vegetatively via rhizomes.
Caution: Whorled milkweed is considered the most toxic of all milkweeds, specifically to livestock. It should not be planted where livestock graze.

Whorled milkweed is occasionally available from nurseries that specialize in Florida native plants. Visit www.PlantRealFlorida.org to find a nursery in your area.

Learn more about Whorled milkweed from the Florida Native Plant Society and the Institute for Regional Conservation.

For information on other Asclepias species, see these resources:

Clasping milkweed

Clasping milkweed (Asclepias amplexicaulis) is a late spring- through summer- blooming milkweed that occurs in dry sandy areas from sandhills to pine savannahs, open woodlands and fallow fields.
Read more… Clasping milkweed

Florida milkweed

Florida milkweed (Asclepias feayi) is a dainty endemic at home in the sandhills and scrubby flatwoods of Central and South Florida. It emerges from winter dormancy in spring and typically blooms mid-summer.
Read more… Florida milkweed

Fewflower milkweed

Fewflower milkweed (Asclepias lanceolata) is a delicate wildflower found in swamps and moist to wet pinelands and prairies throughout Florida. Its stunning orange flowers typically bloom late spring through fall.
Read more… Fewflower milkweed

Swamp milkweed

Swamp milkweed (Asclepias perennis) blooms in late spring through early fall and attracts many pollinators. It is a larval host plant for Monarch, Queen and Soldier butterflies.
Read more… Swamp milkweed
Hummingbird clearwing (Hemaris thysbe) on Swamp milkweed, Asclepias incarnata

Swamp milkweed

Swamp milkweed (Asclepias incarnata ) has showy pink flowers that typically bloom in summer and attract many pollinators. It occurs naturally in floodplain swamps, hydric hammocks, wet pine flatwoods and marshes.
Read more… Swamp milkweed
Savannah milkweed's greenish-yellow, urn-shaped flowers

Savannah milkweed

With its diminutive stature and greenish-yellow flowers, Savannah milkweed (Asclepias pedicellata) is oft overlooked in its native pineland and prairie habitats. It blooms late spring through fall, peaking in summer.
Read more… Savannah milkweed
Green antelopehorn in flower.

Green antelopehorn

Green antelopehorn (Asclepias viridis) is an herbaceous perennial wildflower found in pinelands, pine rocklands and disturbed areas in a few Florida counties. It flowers winter through summer, with peak blooms in spring.
Read more… Green antelopehorn

Longleaf milkweed

Longleaf milkweed (Asclepias longifolia ) is a deciduous perennial wildflower that occurs naturally in bogs, moist to wet flatwoods and prairies. It typically blooms in spring but may bloom well into summer or early fall.
Read more… Longleaf milkweed

Butterflyweed

Butterfly milkweed (Asclepias tuberosa) is a perennial that produces large, showy clusters of bright orange to reddish flowers from spring through fall. It occurs naturally in sandhills, pine flatwoods, and other sandy uplands.
Read more… Butterflyweed