SafePlants

Asclepias incarnata: Swamp Milkweed

Asclepias incarnata, commonly known as swamp milkweed, is a beautiful and beneficial herbaceous perennial. It's a favorite for butterfly gardens and provides essential support for Monarch butterflies.

Common Names

• Swamp Milkweed
• Rose Milkweed
• Rose Milkflower
• Swamp Silkweed
• White Indian Hemp
• Red Milkweed
• Marsh Milkweed
• Pink Milkweed
• Swamp Butterfly Weed

Taxonomy and Nomenclature

• Scientific Name: Asclepias incarnata L.
• Family: Asclepiadaceae (Milkweed Family)
• Synonyms: asclpiade incarnate
• The genus name Asclepias is derived from the name of the Greek god of medicine.

Considerations for Pets

• The text mentions the plant produces a juice, though less milky than other Asclepias species.
• Typical milkweed seed pods develop, which rupture to reveal seeds with long, silvery-white filaments.

Distribution and Habitat

• Native to eastern North America and southern Ontario.
• Commonly found in swamps, river bottomlands, marshes, meadows, fields, shores of rivers or lakes, and other wetland environments.

Morphology and Growth Habits

• An erect, clump-forming perennial wildflower.
• Highly variable in size, typically growing to 2-6 feet tall, or 1-2 feet.
• Consists of a cluster of unbranched flowering stems that are ascending to erect. The stems are light green.
• Leaves are opposite, narrow, and up to 6 inches long.
• Increases in size by sending out underground stems called rhizomes.
• Clusters of upturned pink to rosy red flowers (sometimes red) bloom in summer (June and July).

Ecological Role

• A major host plant for Monarch butterflies, providing a place for them to lay their eggs and food for the larvae.
• Attracts butterflies with its faint vanilla fragrance.
• An important pollinator plant.

Interactions with Other Organisms

• Monarch larvae feed on the leaves, acquiring poisonous chemicals from the plant for their own defense.
• Adults mate on or around milkweed.
• Eggs are cemented to the plant.

Quirky Facts

• A nursery selection of swamp milkweed called Asclepias incarnata 'Ice Ballet' has white flowers.
• One source mentions a color called "Cinderella" that is said to be red to pink.

Further Information

• USDA NRCS, Norman A. Berg National Plant Materials Center
• Dave's Garden: A community that shares tips and ideas for gardens, along with seeds and plants.
• Ontario Wildflowers (for photos and information)