Asclepias incarnata, commonly known as swamp milkweed, is a plant native to Missouri. It is usually found in swamps, river bottomlands, and wet meadows across the state. This plant typically grows 3-4 feet tall on branching stems and produces small, fragrant, pink to mauve flowers with five reflexed petals and an elevated central crown in tight clusters at the stem ends during summer. Flowers are sometimes white. Its narrow, lance-shaped, taper-pointed leaves are 3-6 inches long. When the stems are cut, a toxic milky sap is exuded. After flowering, the plant produces attractive seed pods that split open when ripe, releasing silky-haired seeds easily carried by the wind. Swamp milkweed is a nectar source for butterflies and hummingbirds and a food source for the larval stage of monarch butterflies.

These plants can proliferate in medium to wet soils when planted in full sun. They are surprisingly tolerant of average well-drained soils in cultivation despite the species being native to swamps and wet meadows. Since the plants have deep taproots, it is best to leave them undisturbed once established. Foliage is slow to emerge in the spring.