Centaurea 'Amethyst on Ice'
knapweed 'Amethyst on Ice'
A herbaceous perennial up to 40cm high with broadly lance-shaped green leaves and flowerheads with white ray florets and purple central discs from late spring to late summer; Centaurea flowers are attractive to bees
Size
Ultimate height
0.1–0.5 metresTime to ultimate height
2–5 yearsUltimate spread
0.5–1 metresGrowing conditions
Moisture
Moist but well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Purple White | Green | ||
|---|---|---|---|---|
| Summer | Purple White | Green | ||
| Autumn | Green | |||
| Winter |
Position
- Full sun
- Partial shade
Aspect
West–facing or East–facing or South–facing or North–facing
Exposure
Exposed or Sheltered Hardiness
H7Botanical details
- Family
- Asteraceae
- Native to the UK
- No
- Foliage
- Deciduous
- Habit
- Clump forming
- Genus
Centaurea may be annuals, perennials or subshrubs, with simple or pinnately lobed leaves and showy thistle-like flowers-heads, often with enlarged outer florets
- Name status
Accepted
How to grow
Cultivation
Grow in moist but well-drained soil in sun or partial shade
Propagation
Propagate by division in spring or autumn, or by root cuttings in winter
Suggested planting locations and garden types
- Cottage and informal garden
- Coastal
- Prairie planting
- Low Maintenance
- Cut flowers
- Flower borders and beds
Pruning
No pruning required, but deadheading may help to prolong flowering
Pests
Generally pest-free
Diseases
May be susceptible to powdery mildews but generally disease-free
Get involved
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