Asclepias incarnata
swamp milkweed
A thick-stemmed perennial with dense stems and narrow, mid-green leaves up to 15cm long. Clusters of dark purplish-pink flowers are produced from the upper part of the stems from mid-summer to early autumn, followed by narrow, upright seed pods up to 7cm long, green at first then turning pale brown before splitting to release the seeds with their parachutes
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Size
Ultimate height
1–1.5 metresTime to ultimate height
2–5 yearsUltimate spread
0.1–0.5 metresGrowing conditions
Moisture
Moist but well–drained, Poorly–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green | |||
|---|---|---|---|---|
| Summer | Pink | Green | ||
| Autumn | Pink | Green | Green Brown | |
| Winter |
Position
- Full sun
Aspect
South–facing or West–facing
Exposure
Sheltered Hardiness
H4Botanical details
- Family
- Apocynaceae
- Native to GB / Ireland
- No
- Foliage
- Deciduous
- Habit
- Bushy
- Potentially harmful
- Harmful if eaten. Wear gloves and other protective equipment when handling
- Genus
Asclepias can be evergreen or deciduous perennials or subshrubs, with simple, entire leaves and umbel-like clusters of small, distinctively shaped flowers followed by paired fruits containing seeds embedded in silky fibres
- Name status
Correct
- Plant range
- North America
How to grow
Cultivation
Grow outdoors in moist, fertile, loamy soil in full sun. Will thrive near a pond or stream
Propagation
Propagate by seed or by division, or root basal cuttings in spring
Suggested planting locations and garden types
- Cottage and informal garden
- Prairie planting
Pruning
No pruning required
Pests
Generally pest-free
Diseases
Generally disease-free
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