Asclepias incarnata 'Iceberg'
swamp milkweed 'Iceberg'
An upright, clump-forming perennial to around 90cm in height, with narrow, lance-shaped, dark green leaves. Small, fragrant, waxy pure white flowers with greenish-mustard yellow centres 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
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
Unresolved
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
Generally disease-free
Get involved
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