Asclepias incarnata ‘Swamp Milkweed’

Asclepias incarnata (Swamp Milkweed)

Swamp Milkweed (Asclepias incarnata)—also known as Pink Milkweed, Marsh Milkweed, and Swamp Butterfly Weed—is a native perennial that thrives in wetland habitats. It naturally grows along pond edges, in rain gardens, and in moist meadows. This stunning wildflower plays a vital role in supporting pollinators, especially monarch butterflies, which depend on milkweed as a host plant for their larvae.

This milkweed species grows 3 to 5 feet tall, creating an eye-catching display in summer. Its fragrant pink to mauve flowers bloom in clusters from mid to late summer. These blossoms provide an excellent nectar source for bees, hummingbirds, and butterflies. Unlike common milkweed, it has slender, lance-shaped leaves and does not spread aggressively. Its more compact growth habit makes it ideal for garden borders, butterfly gardens, and naturalized plantings.

Swamp Milkweed thrives in moist, well-drained soil but adapts to drier conditions once established. It prefers full sun but tolerates partial shade. Its deep root system helps prevent soil erosion, making it beneficial for stabilizing wetland areas. The plant also improves biodiversity by supporting various pollinators.

One of its greatest benefits is its ability to attract monarchs. The plant serves as both a nectar source and a crucial larval host. Monarch caterpillars feed exclusively on milkweed, making Asclepias incarnata an essential species for butterfly conservation. Gardeners who wish to support declining monarch populations often plant it for this reason.

Beyond its ecological importance, Swamp Milkweed is easy to grow and requires minimal maintenance. It resists deer and pests, reducing the need for intervention. In late summer, the plant develops seed pods that release silky seeds, carried by the wind to new locations.

For best results, plant Swamp Milkweed in consistently moist soil with good drainage. It can be propagated by seed or root division. If growing from seed, a cold stratification period enhances germination. Whether planted in rain gardens, along stream banks, or in sunny garden beds, this beautiful and beneficial wildflower enriches any landscape.