Allium tuberosum blue-flowered
flat-stalked garlic
Bulbous perennial about 60cm tall, with broad, grey-green basal leaves in clumps to 30cm. Numerous flowers in spherical umbels are variable in colour from rose-pink to mauve-blue and white and are borne in early or mid summer; suited to wet soils. The image shown is Allium nutans 'Caroline'
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 | Pink Purple Blue White | Green | ||
| Autumn | ||||
| Winter |
Position
- Full sun
Aspect
West–facing or South–facing
Exposure
Exposed or Sheltered Hardiness
H6Botanical 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
- Russia
How to grow
Cultivation
Grow in moist but well-drained, reasonably fertile soil in full sun. Happy in moist soils, unlike most allium species. See allium cultivation for further advice
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
- Wildlife gardens
- Patio and container plants
- 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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