Asclepias incarnata 'White Superior'
swamp milkweed 'White Superior'
A fast-growing, clump-forming perennial to around 1m in height, with narrow, lance-shaped, dark green leaves. Small, fragrant, waxy pure white flowers appear in dense clusters on sturdy stems from midsummer into autumn. These are followed by seed pods that split to release silky-haired seeds. A great choice for cutting
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Size
Ultimate height
0.5–1 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 | White | Green | ||
| Autumn | White | Green | ||
| 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
Accepted
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
- City and courtyard gardens
- Cottage and informal garden
- Prairie planting
- Cut flowers
- Flower borders and beds
Pruning
No pruning required
Pests
Generally pest-free
Diseases
Geneally disease-free
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