Asclepias Perennis
Aquatic Milkweed for Monarch Caterpillars and Pollinators
Asclepias perennis: Aquatic milkweed, Swamp Milkweed, White milkweed, White Swamp Milkweed

Plant Specs:
- Perennial: USDA hardiness zones 6a-9b (lows -23.3 °C or -10 °F)
- Native to much of the central to southeastern US (Al, Ar, Fl, Ga, Il, In, Ky, La, Ms, Mo, SC, Tn, Tx)
- Full sun to part shade
- Height: 1 to 3 feet
- Spacing: 1 to 2 ft
- Milkweed Flowers: white to light pink flowers that resemble ‘ice ballet’ incarnata
- Milkweed leaves: green leaves attached to short petioles
- Blooms late spring to fall- blooms repeatedly over season
- Grows wild in marshes, ditches, wetlands, near ponds and rivers
Plant Propagation:
- Sow seeds outside in fall– November is a good option for most regions
- Take Stem Cuttings and start in water or directly in soil
- Winter sowing is a good option if you want to control plant placement
- Start seeds indoors 2 months before final frost- seeds must be cold stratified
- Spring sow directly after final frost
Pros:
- Good choice for rain gardens or by water features
- Large, thick leaves can sustain more monarch caterpillars
- Supports a wide range of pollinators
- Easy to start from stem cuttings milkweed seeds
- Fibrous roots transplant easily
- Long bloom period and can rebloom
Cons:
- Short plants can get overtaken in the garden without proper spacing
- Prone to aphid pests like most milkweed
- Can remain evergreen in continuous growing regions and spread OE disease to monarchs
Aquatic Growing Tips:

- Grow in containers to keep shorts plant easily visible and portable
- Transplant milkweed in early spring or fall for a higher survival rate
- Seed Saver- If you don’t want additional seedlings next spring, simply cut off the seed pods before they pop open or bind them shut with organza bags if you want to collect common milkweed seeds

Pollinator Plus:
This milkweed also attracts queen and soldier butterflies that also use this milkweed as a host plant for growing caterpillars. Aquatic milkweed also attracts bees, wasps, and other beneficial insects. We will watch be watching perennis plants for other visitors this season. If you know of other pollinators that utilize aquatic milkweed, please comment below.
Buying Tip: Common names can cause confusion and you’ll end up buying the wrong plants. Swamp milkweed is also commonly used to label Asclepias incarnata, so always use the scientific/botanical name when purchasing milkweed seeds and plants.
Asclepias Perennis Resources:
1. Buy Asclepias Perennis at Joyful Butterfly
2. Get Asclepias Perennis on Etsy
3. Find Aquatic Milkweed on Amazon
Click here for 30+ Milkweed Varieties for your Butterfly Garden
We’re moving to OH from FL and we’ve had a butterfly garden for years. Which Milkweed is native to the OH region?
Hi Ron, check out our milkweed page for 30 milkweed options listed with native/perennial regions. Happy gardening!