Centaurea cyanus 'Blue Diadem'
Cornflower, Blue-bottle, Batchelor's buttons
- Height × spread
- 0.75m × 0.3m
- Position
- Full sun
- Hardiness
- Very cold to -20C (RHS H6)
- Flowers
- Spring, Summer
Availability
Please ask in store about availability
Many plants are seasonal. Call 01234 567890 to check current stock.
About this plant
Slender rather swaying stems carry double pom pom flowers dark blue with purple at the petal base. The foliage has long slender leaves that are grey green. It flowers in spring and early summer and will probably self seed. This variety grows to around 75cm (2ft 6in) high with a 30cm (1ft) spread. Give it a sunny site and well drained soil.
- Flower colour
- Blue
- Foliage colour
- Grey
- Variegated
- No
- Scent
- Yes, sweet-lilac
- Shape
- Bell
- Height
- 0.75m
- Spread
- 0.3m
- Season of interest
- Spring, Summer
- Flowers in
- Spring, Summer
- Evergreen
- Deciduous
- Garden style
- Seaside garden, Prairie garden, Cottage garden
- Sun or shade
- Likes full sun
- Soil type
- Gravelly soil, Loam (normal), Poor soil, Sandy soil
- Soil pH
- All types
- Drainage
- Well drained soil, Dry soil, Drought resistant
- Hardiness
- Very cold to -20C (RHS H6)
- Borders & containers
- Borders
- Use for
- Bedding plant, Bee attraction, Butterfly attraction, Bird attraction
- Hazards
- No
Spring
Spring-Autumn · Outdoors
Water in dry periods
Established plants in the ground can cope with 7-10 days of dryness, and shrubs often manage 2 to 3 weeks. Water one section of the garden thoroughly each day rather than a little everywhere. Check plants in pots more often, especially in hot weather.
Summer
Summer - early · Outdoors
Feed a general fertiliser
Where plants have moderate needs for nutrients, they can simply be given a general feed, fairly early in the growth season so that the growth has plenty of time to harden off before the cold weather.
Give plants a general boost with the application of a general purpose fertiliser which is spread around the root area of the plant, with amounts as directed on the feed label.
Found in
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