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Allium caeruleum

blue allium bulbs (syn. Allium azureum)

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This stunning blue ornamental onion is ideal for a sunny border. Dense globes of small, star-shaped, bright blue summer flowers on stiff stems and narrow, mid-green leaves. Since the leaves die back before the flowers emerge it’s best planted with other medium-sized herbaceous plants, such as sea holly, which help to mask the faded foliage.

How to care for Allium caeruleum:

Allium bulbs are easy to grow in a sunny spot with freely drained soil, or a good quality potting compost. Ideally they should be planted in September or October, but could also be planted in early November in milder regions. Dig holes roughly three times as deep as the diameter of the bulb and place them at the base, pointy side up before gently infilling and watering to settle them in. In early spring, as growth begins, apply a balanced, slow-release fertiliser, and allow the plants to die back naturally and completely before tidying away.
Flowering period:
  • Jan
  • Feb
  • Mar
  • Apr
  • May
  • Jun
  • Jul
  • Aug
  • Sep
  • Oct
  • Nov
  • Dec
Eventual height:
0.6m
Eventual spread:
0.25m
Position:

Full sun

Rate of growth:

Average

Soil:

Moderately fertile, moist, well-drained soil

Hardiness:

Fully hardy

  • InformationPets: TOXIC if eaten; Humans: Ornamental bulbs - not to be eaten

Product options

Product options image
BU30000214
20 × bulbs
£7.99
available to order from summer
Product options image
BU30000215
40 + 20 FREE bulbs
was £23.97 now £15.98
available to order from summer
Delivery options (pick your preferred option at checkout)
Standard delivery Bulbs (only)£4.95

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