Swamp Milkweed (Asclepias incarnata)
Milkweed is the essential host plant for monarch caterpillars and a nectar source for many pollinators. All of our milkweeds are hardy perennials that return year after year once established.
plant profile
Swamp Milkweed is an elegant native perennial with narrow leaves and clusters of fragrant pink flowers. Naturally found in wetlands, marshes, stream banks, and other moist areas, it thrives in locations where the soil stays consistently moist. Its upright growth and showy flowers also make it an attractive addition to rain gardens and traditional garden beds.
Growing conditions
- Size: 3 to 5 feet tall, 2 to 3 feet wide
- Light: Full sun
- Soil: Moist, well drained to wet soil
- Water: Moderate to high; prefers consistent moisture
- Bloom time: Summer
- Lifecycle: Perennial
planting instructions
- Plant in spring or fall when temperatures are mild
- Dig a hole slightly wider than the root ball and set the crown level with the soil surface
- Space plants 18–24 inches apart
- Water thoroughly after planting and regularly while the plant becomes established. Continue to provide supplemental water as needed to keep soil consistently moist.
- Choose a location where the soil naturally retains moisture or provide additional water during dry periods.
seasonal growth pattern
- Year 1: Focuses on establishing its root system and top growth; flowering may be limited while the plant becomes established.
- Year 2: Produces stronger growth and more reliable flowering.
- Year 3 and beyond: Returns reliably each spring with established growth and produces clusters of pink flowers during summer.
- Fall & Winter: Seed pods mature and split to release wind dispersed seeds. Above ground growth dies back for winter and returns in spring.
care
Swamp Milkweed performs best in full sun and consistently moist soil. Once established, it tolerates wet conditions well but may need supplemental watering during extended dry periods. Avoid allowing the soil to remain excessively dry for long periods.
notes
- Naturally adapted to wetlands, marshes, stream banks, and other moist areas.
- An excellent choice for rain gardens and other areas that naturally retain moisture.
- Produces fragrant clusters of pink flowers.
- Unlike more drought tolerant milkweeds, Swamp Milkweed performs best when consistent soil moisture is available.