Pictured above: Curtiss’ milkweed (Asclepias curtissii) by Emily Bell. Click on terms for botanical definitions. View post as a PDF.
Curtiss’ milkweed (Asclepias curtissii) is a long-lived and somewhat mysterious milkweed endemic to the Florida scrub. The populations of this state-endangered wildflower are widely scattered and sometimes only a single plant will be found within a site. Its population dynamics have been challenging to study because it is very difficult to find when not in bloom and it can remain dormant through more than one season.
Curtiss’ milkweed is deciduous. Its woody stem can grow up to 4 feet long and typically leans, giving it an almost vine-like sprawl. Its leaves are dark green, oval, undulate and oppositely arranged. Flower umbels are born in the axils of the leaves and typically bloom in summer. Individual flowers have light green to tan reflexedcorollas and a white upright corona with a light pink to purple tip.
Photo by Emily Bell
Photo by Emily Bell
Like all members of the Asclepias genus, Curtiss’ milkweed is a larval host plant for Monarch, Queen and Soldier butterflies. However, the levels of poisonous cardenolides that the caterpillars are adapted to feed on but typically deter other browsers are low in Curtiss’ milkweed and therefore it is sometimes foraged by deer. Learn more about Monarchs and Milkweed in Florida here.
Family: Apocynaceae (Dogbane family) Native range: Peninsular Florida To see where natural populations of Curtiss’ milkweed have been vouchered, visit florida.plantatlas.usf.edu. Lifespan: Perennial Soil: Deep, extremely well-drained sand Exposure: Full sun Growth habit: Up to 4 feet, often leaning
Curtiss’ milkweed is not commercially available. Visit a natural area to see it.
For more information on other Asclepias species, see these resources:
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.
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.
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.
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.
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.
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.
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.
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.
Pinewoods milkweed (Asclepias humistrata) occurs naturally in sandhills, scrub and dry, ruderal areas. It blooms in spring and summer, attracting many pollinators including wasps and butterflies.
Whorled milkweed (Asclepias verticillata ) is one of the smaller, more delicate native milkweeds and is easily overlooked when not in bloom. It flowers late spring through summer and into early fall.
Largeflower milkweed (Asclepias connivens ) is a perennial wildflower found throughout much of Florida. Its conspicuous flowers appear in late spring through summer in moist pine flatwoods, savannahs and bogs.
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.
