Centaurea scabiosa

greater knapweed
C. scabiosa is an upright perennial to 75cm, with pinnately lobed leaves and reddish-purple flowers heads to 5cm across, usually with enlarged outer florets
Other common names
black topSynonyms
Centaurea scabiosa var. petrophilaBuy this plant
Size
Ultimate height
0.5–1 metresTime to ultimate height
2–5 yearsUltimate spread
0.1–0.5 metresGrowing conditions
Moisture
Moist but well–drainedpH
Acid, Alkaline, NeutralColour & scent
Stem | Flower | Foliage | Fruit | |
Spring | Green | |||
---|---|---|---|---|
Summer | Purple Red | Green | ||
Autumn | Green | |||
Winter |
Position
- Full sun
- Partial shade
Aspect
West–facing or South–facing or North–facing or East–facing
Exposure
Exposed or Sheltered Hardiness
H6Botanical details
- Family
- Asteraceae
- Native to the UK
- Yes
- 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
Correct
- Plant range
- Europe
How to grow
Cultivation
Prefers a well-drained fertile soil in a sunny position. Tolerant of dry, alkaline soils and established plants are tolerant of considerable neglect. Self-seeds readily and can become invasive
Propagation
Suggested planting locations and garden types
- Wildlife gardens
- Wildflower meadow
- Low Maintenance
Pruning
No pruning required
Pests
Generally pest free. Resistant to browsing by deer
Diseases
May be affected by powdery mildews
Get involved
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