Swamp milkweed is an erect, clump-forming, native plant which is commonly found in swamps, river bottomlands and wet meadows. It typically grows 3-4′ tall (less frequently to 5′) on branching stems. Small, fragrant, pink to mauve flowers (1/4″ wide), each with five reflexed petals and an elevated central crown, appear in tight clusters (umbels) at the stem ends in summer. Flowers are uncommonly white. Narrow, lance-shaped, taper-pointed leaves are 3-6″ long. Stems exude a toxic milky sap when cut. Flowers are followed by attractive seed pods (to 4″ long) which split open when ripe releasing silky-haired seeds easily carried by the wind. Flowers are very attractive to butterflies as a nectar source. In addition, Swamp Milkweed is an important food source for the larval stage of Monarch butterflies.
Easily grown in medium to wet soils in full sun. This deer-resistant plant grows best in moist but will tolerate average soils, and blooms for about a month mid-summer. Flowers have a lovely vanilla fragrance that lasts into the fall after the flowerheads have dried. Plants have deep taproots and are best left undisturbed once established. Foliage is slow to emerge in spring.