A showy two foot tall perennial with fragrant, terminal blossoms made up of tiny rosy-purple blossoms. This milkweed prefers average to very moist soils, will tolerate heavy clay soils and is easy to start from seed and deer resistant. This hardy perennial, whose scientific name comes from the Greek god of medicine, is a favorite of butterflies, native bees and hummingbirds. The seeds are very easy to grow and do well when planted in the fall or when cold-treated for three month prior to planting. Swamp Milkweed will spread through seed distribution and underground shoots. Monarch Butterflies and Queen Butterflies lay their eggs on the milkweed and the larvae feed on the plants. Note that these plants contain cardiac glycosides, chemicals, that are toxic when eaten and make the Butterflies also toxic to any would be predators. These will spread easily and may need to be controlled. These are good for wetland rehabilitation and as a component in wildlife seed mixtures.