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BulbsHerbs - Culinary

Allium fistulosum 'Photon'
  • RHS Plants for pollinators

onion (salad) 'Photon'

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. Noted for its exceptionally long harvest period from June to October 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

Size
Ultimate height
0.1–0.5 metres
Time to ultimate height
1–2 years
Ultimate spread
0.1–0.5 metres
Growing conditions
Chalk
Loam
Sand
Moisture
Moist but well–drained, Well–drained
pH
Acid, Alkaline, Neutral
Colour & scent
StemFlowerFoliageFruit
Spring White Green White Green
Summer White Green
Autumn White Green
Winter White Green
Position
  • Full sun
Aspect

South–facing or West–facing

Exposure
Sheltered
Hardiness
H5
Botanical details
Family
Amaryllidaceae
Native to GB / Ireland
No
Foliage
Evergreen
Habit
Clump forming
Potentially harmful
TOXIC to pets - 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

Unresolved

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 slugs, snails and allium leaf miner

Diseases

May be susceptible to onion white rot, and onion downy mildew

Get involved

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