Often called, Swamp Milkweed, this pretty blend of pink and white Asclepias incarnata flowers is perennial to USDA zone 3. The blooms have a soft vanilla scent and tempt butterflies, hummingbirds, and beneficial insects to the garden to feast on nectar. It is a host plant for butterflies. They lay their eggs on it, and it provides food for the caterpillars. It makes a wonderful cut flower, and its decorative green seedpods can be saved for dried arrangements. Unlike the common and drought-tolerant Butterfly Flower (Asclepias tuberosa), this tall, 3'-5' variety prefers moist soil, such as near a pond or stream, but the loosely clumped plants will grow in a garden with regular watering.