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Allium suworowii
  • RHS AGM
  • RHS Plants for pollinators

Bulbous perennial to 1m tall, with strap-shaped mid to grey green leaves and vibrant, deep purple starry flowers in globular flowerheads produced in May and June on strong, upright stems

Size
Ultimate height
0.5–1 metres
Time to ultimate height
1–2 years
Ultimate spread
0–0.1 metre
Growing conditions
Chalk
Loam
Sand
Moisture
Well–drained
pH
Acid, Alkaline, Neutral
Colour & scent
StemFlowerFoliageFruit
Spring Purple Grey Green
Summer Purple Grey Green
Autumn
Winter
Position
  • Full sun
Aspect

South–facing or West–facing or East–facing

Exposure
Sheltered
Hardiness
H5
Botanical 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

How to grow

Cultivation

Easy to grow in fertile well-drained soil in full sun. See allium cultivation for further advice

Propagation

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
  • 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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