Allium fistulosum 'Long White Ishikura'
onion (salad) 'Ishikura'
Evergreen, perennial onion, grown as an ornamental in the herb or wildlife garden or as an annual vegetable, forming clumps of elongated, straight white stems and hollow green leaves. Exceptionally long harvest period from summer to autumn without the need for successive sowings. In their second year, the bulbs produce spherical heads of densely clustered greenish-white flowers on stems to 60cm high in early and midsummer
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Size
Ultimate height
0.1–0.5 metresTime to ultimate height
1–2 yearsUltimate spread
0.1–0.5 metresGrowing conditions
Moisture
Moist but well–drained, Well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | White | Green | ||
|---|---|---|---|---|
| Summer | White | Green White | Green | |
| Autumn | Green | |||
| Winter | White | Green |
Position
- Full sun
Aspect
South–facing or West–facing
Exposure
Sheltered Hardiness
H5Botanical details
- Family
- Amaryllidaceae
- Native to GB / Ireland
- No
- Foliage
- Evergreen
- Habit
- Clump forming
- Potentially harmful
- TOXIC to pets (dogs and cats). See the HTA guide to potentially harmful plants for further information and useful contact numbers
- 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
Accepted
How to grow
Cultivation
Easy to grow in full sun and a 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. See sowing vegetable seeds
Suggested planting locations and garden types
- Cottage and informal garden
- Patio and container plants
- Wildlife gardens
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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