Centaurea cyanus Polka Dot Series
A collection of annual cornflowers, to around 50cm high in flower, with lance-shaped, grey-green leaves. Showy flower-heads, in a wide range of colours from white to pinks, reds, purples and blues, are produced all through the summer
Size
Ultimate height
0.1–0.5 metresTime to ultimate height
1 yearUltimate spread
0.1–0.5 metresGrowing conditions
Moisture
Well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green Grey Silver | |||
|---|---|---|---|---|
| Summer | White Pink Red Blue Purple | Green Grey Silver | ||
| Autumn | ||||
| Winter |
Position
- Full sun
Aspect
South–facing or West–facing
Exposure
Exposed or ShelteredDrought resistance
Yes Hardiness
H6Botanical details
- Family
- Asteraceae
- Native to GB / Ireland
- 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 almost any well-drained soil in full sun. Thrives in poor soils but will not tolerate waterlogging
Propagation
Propagate by seed (sown outdoors) in early spring. Sow successionally rather than all at once for a longer show of flowers
Suggested planting locations and garden types
- Coastal
- Cottage and informal garden
- Patio and container plants
- Wildflower meadow
- Wildlife gardens
- Cut flowers
- Flower borders and beds
Pruning
Deadhead to encourage more flowers, unless seed is required
Pests
Generally pest-free
Diseases
May be susceptible to downy mildews, powdery mildews and rust diseases
Get involved
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