Allium caeruleum (Ornamental Onion)
Allium Caeruleum, Allium azureum, Allium caeruleum azureum, Allium Coerulescens, Azure-Flowered Garlic, Blue-Flowered Garlic, Flowering Onion, Ornamental Onion, Spring Bulbs, Spring Flowers
Award-winner Allium caeruleum is a stunning ornamental onion with its inflorescence consisting of dozens of small star-shaped bright blue flowers forming a 1-inch wide (3 cm) globe-shaped cluster atop stiff stems and narrow green leaves. Prized for its true blue color, Allium caeruleum provides interesting ornamental value in the garden in late spring to early summer.
- Growing up to 12-24 in. tall (30-60 cm), Allium caeruleum forms dense, slowly-spreading clumps over time. It naturalizes easily and will come back year after year! Since the leaves wither before the flowers emerge, plant your Allium caeruleum with other mid-sized plants to hide the faded foliage.
- Awarded the prestigious Award of Garden Merit by the Royal Horticultural Society
- Easily grown in rich, sandy to gritty, dry to medium moisture, well-drained soils in full sun. Drought tolerant.
- Attracts butterflies, but deer ignore it!
- Stunning in beds, borders, cottage gardens. Spectacular in large sweeping drifts. For best visual impact, plant in groups (at least 10 to 15 bulbs). Excellent as cut flowers for both fresh and dried arrangements!
- Mixes beautifully with other late spring flowering bulbs and creates stunning combinations with pink or white Delphiniums, Peonies or Irises.
- To be planted in fall.
Many hundreds of Allium species exist, but only a modest few have made a name for themselves as garden plants. The ornamental onions distinguish themselves by their great diversity in color, inflorescence and flowering height. Many species bloom in early summer - just after the spring-flowering period and just before the exuberant full bloom of summer. All species can be used in the border. Certain small species are just perfect for a rock garden, and several lend themselves to naturalizing.
Learn How To Plant And Care for Your Spring Flower Bulbs
To achieve optimum flowering results, it is important to plant the bulbs at the right time.
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Requirements
Hardiness | 4
– 10 |
---|---|
Heat Zones | 1
– 10 |
Climate Zones | 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 |
Plant Type | Bulbs |
Plant Family | Alliums |
Exposure | Full Sun |
Season of Interest |
Spring (Late) Summer (Early) |
Height | 1' – 2' (30cm – 60cm) |
Spread | 6" – 1' (15cm – 30cm) |
Spacing | 2" (5cm) |
Depth | 4" (10cm) |
Water Needs | Average |
Maintenance | Low |
Soil Type | Chalk, Clay, Loam, Sand |
Soil pH | Acid, Alkaline, Neutral |
Soil Drainage | Moist but Well-Drained, Well-Drained |
Characteristics | Cut Flowers, Fragrant, Plant of Merit, Showy |
Tolerance | Deer, Drought, Rabbit |
Attracts | Butterflies |
Garden Uses | Beds and Borders, Underplanting Roses and Shrubs |
Garden Styles | Informal and Cottage |
ikrolevetc / 123RF Stock Photo
While every effort has been made to describe these plants accurately, please keep in mind that height, bloom time, and color may differ in various climates. The description of these plants has been written based on numerous outside resources.
Requirements
Hardiness | 4
– 10 |
---|---|
Heat Zones | 1
– 10 |
Climate Zones | 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24 |
Plant Type | Bulbs |
Plant Family | Alliums |
Exposure | Full Sun |
Season of Interest |
Spring (Late) Summer (Early) |
Height | 1' – 2' (30cm – 60cm) |
Spread | 6" – 1' (15cm – 30cm) |
Spacing | 2" (5cm) |
Depth | 4" (10cm) |
Water Needs | Average |
Maintenance | Low |
Soil Type | Chalk, Clay, Loam, Sand |
Soil pH | Acid, Alkaline, Neutral |
Soil Drainage | Moist but Well-Drained, Well-Drained |
Characteristics | Cut Flowers, Fragrant, Plant of Merit, Showy |
Tolerance | Deer, Drought, Rabbit |
Attracts | Butterflies |
Garden Uses | Beds and Borders, Underplanting Roses and Shrubs |
Garden Styles | Informal and Cottage |