Pronunciation: as-KLEE-pee-as pur-pur-ESS-kenz
Rich reddish-purple flowers crown this native milkweed. Broad opposite leaves, mostly terminal flower clusters and smooth-sided seed pods help distinguish it from Common Milkweed.
Family: Apocynaceae (Dogbane)
Genus: Asclepias
Life cycle: Perennial
Height: Usually 2–4 feet
Bloom: Mainly June–July in the Upper Midwest
Light: Sun to partial shade
Habitats: Open oak woods, woodland edges, savannas, prairie openings and roadsides. [1, 2]
01 · Rose-purple flowers with pale upright hoods above swept-back petals
02 · Broad, pointed leaves in opposite pairs
03 · One or a few flower clusters near the top of the stem
Look in open oak woods, woodland margins, savannas and prairie openings. In Wisconsin, flowering generally falls in June and July. This species occurs across a range of soil moisture conditions; use the leaves and flowers along with the setting to identify it. [1, 6]
Include the upper stem and the leaves below the flowers. Purple Milkweed usually carries a terminal cluster, sometimes with one or two more near the upper leaves. Photograph an open flower and a leaf attachment as well; flower color alone is not enough for identification. [1, 3]
Two short-stalked leaves meet the stem at the same node. Their blades are broad and taper toward pointed tips, with smooth, untoothed edges that may look wavy. Fine hairs cover the underside. Trace each leaf back to the stem so neighboring plants do not confuse the paired arrangement. [1, 5]
The five pale pink to purple hoods stand above the darker petals, which bend backward. Each hood contains a short, inward-curving horn that is usually concealed or only barely projects. This helps separate Purple Milkweed from Swamp Milkweed, whose horns extend conspicuously above its hoods. Enlarge the photograph to inspect the flower. [1, 3]
The slender green pods taper to long points. Their surfaces lack the soft prickles of Common Milkweed, although fine hairs may be present. Mature pods split to release seeds with silky tufts. Pods provide another useful clue, but compare them with foliage and flower records whenever possible. [5, 6]
The first two identification cards use AI-created educational artwork for general plant and habitat views. The flowering-stem and detail cards use field photographs. Use the photographs and written features for close identification. Select any image to enlarge it.
Common Milkweed: Usually has paler flowers in clusters along the upper stem, broader rounded leaf tips and pods with soft prickles.
Swamp Milkweed: Usually has much narrower leaves and smaller pink flowers; its floral horns project more prominently above the hoods.
Flower color alone is not enough: compare flower structure, leaves, cluster position and fruit together. [3]
Native to southeastern Canada and the central and eastern United States, including Illinois and Wisconsin. Look in open woods, woodland margins and prairie or savanna openings. [1, 4]
Wildlife connection: Purple Milkweed feeds Monarch caterpillars and offers nectar to visiting bees and butterflies. [5]
Observation maps show reported sightings, rather than the full native range.
