Allium fistulosum 'Summer Isle'
onion (salad) 'Summer Isle'
A bulb-forming perennial usually grown as an annual for its edible shoots. This late-maturing bunching or salad onion has a mild, sweet flavour and a good length of blanched stem. It can also have some ornamental value if left to flower, producing tightly clustered flower heads that are popular with bees
Size
Ultimate height
0.1–0.5 metresTime to ultimate height
1 yearUltimate spread
0–0.1 metreGrowing conditions
Moisture
Moist but well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green | |||
|---|---|---|---|---|
| Summer | White Purple | Green | ||
| Autumn | White Purple | Green | ||
| Winter |
Position
- Full sun
- Partial shade
Aspect
East–facing or South–facing or West–facing
Exposure
Exposed or Sheltered Hardiness
H3Botanical details
- Family
- Amaryllidaceae
- Native to GB / Ireland
- No
- Foliage
- Evergreen
- 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
Unresolved
How to grow
Cultivation
Easy to grow in fertile, well-drained soil. See how to grow: salad onions for further advice
Propagation
Propagate by seed. See sowing vegetable seeds
Suggested planting locations and garden types
- Wildlife gardens
- Cottage and informal garden
Pruning
To harvest as a vegetable, lift the whole plant before flowering stems form. For ornamentals, remove faded flower heads to prevent self-seeding
Pests
Diseases
May be susceptible to onion white rot and downy mildew
Get involved
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