Swamp Milkweed

Swamp Milkweed

Botanical Name: Asclepias incarnata

En Français: Asclépiade rouge


This milkweed species is known for its ability to thrive in swampy areas and wet meadows. Despite its love of wet soils, due to its long taproot, it can tolerate average well-drained soils with ease. Pink and white duo-tone flowers are displayed throughout the summer months.

Grows up to 1.5m tall, though height can vary considerably. Most often found growing in full sun or partial shade in moist or damp soils, such as along lakes, rivers, swamps, or drainage ditches. Does not grow in areas that are typically hot and dry. Unlike common milkweed, the central stem may branch. Leaves can be up to 15cm in length (but are often shorter), are much narrower (1-4cm width) than common milkweed, and taper to a sharper point.

Flowers are very attractive to butterflies as a nectar source. In addition, swamp milkweed is an important food source (albeit somewhat less important than upland species of Asclepias) for the larval stage of Monarch butterflies.

Other Characteristics

Pollinators: Butterflies

Sun/Shade: Full Sun

Planting and Care Considerations

Easily grown in medium to wet soils in full sun. Surprisingly tolerant of average well-drained soils in cultivation even though the species is native to swamps and wet meadows. Plants have deep taproots and are best left undisturbed once established. Foliage is slow to emerge in spring.

They mingle easily with other sun & moisture lovers

Spread: Up to 90 cm

Water: Medium to wet

Best Soil: Clay, Loam

Growth Habit: 

More Information

Milkweed is a flowering plant essential to the life cycle of the monarch, as it is the sole source of food for the caterpillars.