Swamp Milkweed is an erect, clump-forming perennial prized for its brilliant clusters of vanilla scented, rose-pink flowers, which bloom continuously for weeks from midsummer to early fall. The flowers are a great source of nectar for butterflies, hummingbirds, bees and other beneficial insects. Sitting atop upright branching stems, clad with stiff lance-shaped, taper-pointed leaves, the colourful umbels give way to attractive seed pods in the fall, which persist into winter. A great choice for the flower garden. Full sun. Hardy to USDA Zones 3-9.