Centaurea cyanus 'Black Ball'
Cornflower, Blue-bottle, Batchelor's buttons
- Height × spread
- 0.8m × 0.2m
- Position
- Full sun
- Hardiness
- Very cold to -20C (RHS H6)
- Flowers
- Summer
Availability
Please ask in store about availability
Many plants are seasonal. Call 01234 567890 to check current stock.
About this plant
This striking annual combines fresh silvered green grassy foliage with cornflower blooms that are coloured a dark maroon. This makes for an unusual, some might say, sophisticated contrast that can add interest to a garden. This is summer flowering and looks good grown in a group where it can be contrasted with orange shades, or is good with blues and silvers.
- Flower colour
- Purple
- Foliage colour
- Green
- Variegated
- No
- Scent
- Yes, sweet-lilac
- Shape
- Column
- Height
- 0.8m
- Spread
- 0.2m
- Season of interest
- Summer
- Flowers in
- Summer
- Evergreen
- Deciduous
- Garden style
- Seaside garden, Prairie garden, Cottage garden
- Sun or shade
- Likes full sun
- Soil type
- Loam (normal)
- Soil pH
- All types
- Drainage
- Well drained soil, Dry soil, Drought resistant
- Hardiness
- Very cold to -20C (RHS H6)
- Borders & containers
- Borders and containers
- Use for
- Ground cover, 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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