Swamp Milkweed, PA Ecotype

Asclepias incarnata (Swamp Milkweed) is an erect-growing, clump-forming native that typically grows to 4.9 ft. with sticky, milky sap associated with milkweeds. The stems of Swamp Milkweed are smooth or sparsely hairy. Leaves of Asclepias incarnata grow in an opposite arrangement on the stems. Swamp Milkweed blooms in midsummer with pink and occasionally white flowers that form at the tip of the stems. Asclepias incarnata flowers emit the scent of bubblegum when sunlight strikes them. Seed pods of Swamp Milkweed form in a candelabra-like arrangement. Asclepias incarnata grows in full sun in damp soils of wet meadows, swamps, and floodplains. Swamp Milkweed is a host plant for monarch butterfly caterpillars and the species on which we observe the most caterpillars and chrysalis in our production fields. In addition to supporting monarch caterpillars, Asclepias incarnata provides nectar for many species of native bees and butterflies. Swamp Milkweed is a beautiful addition to rain garden, retention basin, riparian, wet meadow, and wetland mixes. Aphids can overwhelm Asclepias incarnata, so we do not recommend planting it in a monoculture. Since seed dormancy can be high for individual lots of Swamp Milkweed, we recommend three months of cold, moist stratification to break dormancy for transplant production. Asclepias incarnata is a member of the milkweed (Asclepiadaceae) family. The genus name Asclepias is derived from Asklepios, the Greek god of medicine, while the species name incarnata means flesh colored.