Allium cyaneum
dark blue garlic
Bulbous perennial to 25cm, spreading by short rhizomes to make a clump, with sparse, narrow dark green leaves and small heads of intense violet-blue flowers
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Size
Ultimate height
0.1–0.5 metresTime to ultimate height
2–5 yearsUltimate spread
0–0.1 metreGrowing conditions
Moisture
Moist but well–drained, Well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green | |||
|---|---|---|---|---|
| Summer | Blue | Green | ||
| Autumn | ||||
| Winter |
Position
- Full sun
Aspect
South–facing or West–facing
Exposure
Sheltered Hardiness
H7Botanical details
- Family
- Amaryllidaceae
- Native to GB / Ireland
- No
- Foliage
- Deciduous
- Habit
- Clump forming
- Genus
Allium are bulbous herbaceous perennials with a strong onion or garlic scent, linear, strap-shaped or cylindrical basal leaves and star-shaped or bell-shaped flowers in an umbel on a leafless stem
- Name status
Correct
- Plant range
- SW China
How to grow
Cultivation
Grow in full sun and fertile well-drained soil. It is best to grow in containers where garden soil is heavy clay and prone to saturation over winter. See allium cultivation
Propagation
Propagate by seed when just ripe or in spring; or propagate by offsets which can be carefully detached by lifting the bulb after flowering has finished. See bulb propagation
Suggested planting locations and garden types
- City and courtyard gardens
- Coastal
- Cottage and informal garden
- Gravel garden
- Patio and container plants
- Rock garden
- Wildlife gardens
- Flower borders and beds
Pruning
No pruning required, other than to remove old flowered stems and foliage
Pests
May be susceptible to allium leaf miner and onion fly
Diseases
May be susceptible to onion white rot, and onion downy mildew
Get involved
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