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Allium caeruleum AGM

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Characteristics

Plant type

Bulb

Fragrance

Leaf

Toxicity

Resilience

Hardiness

H5 (hardy - cold winter)

Colour

Flower

Blue in Summer

Foliage

Green in Spring

Size

Ultimate height

0.5-1 metres

Ultimate spread

0-0.1 metre

Time to ultimate height

2-5 years

Preferred common name

blue-flowered garlic

Family

Alliaceae

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

A. caeruleum is a bulbous perennial up to 80cm in height, with narrow leaves often withering by flowering time. Starry blue flowers are borne in compact, rounded clusters in early summer

Other common names

azure-flowered garlic

Synonym(s)

Allium azureum
Allium caeruleum azureum
Allium coerulescens

Suppliers

Suppliers listed in RHS Plant Finder

Awards

Award of Garden Merit

How to grow

Sunlight

Full sun

Aspect

South-facing, North-facing, West-facing or East-facing

Sheltered

Cultivation

Easy to grow in fertile well-drained soil. Add grit when grown in clay soils to improve drainage

Soil

Well-drained or Moist but well-drained

Acid, Alkaline or Neutral

Chalk, Clay, Sand or Loam

Propagation

Propagate by seed, sowing in containers in a cold frame when just ripe or in the spring. Alternatively, remove offsets in autumn

Suggested planting locations and garden types

Cottage/Informal Garden, Flower borders and beds, Cut Flowers or Underplanting of Roses and Shrubs

How to care

Pruning

No pruning required

Pests

Generally pest free

Diseases

Generally trouble-free: Onion white rot and a downy mildew may occur

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