Allium Species, Blue Ornamental Onion, Blue-of-the-Heavens, Blue-flowered Garlic
Alliumcaeruleum

Synonym:Allium azureum

Synonym:Allium caerulescens

Synonym:Allium viviparum

Category
Bulbs

Water Requirements
Drought-tolerant; suitable for xeriscaping
Average Water Needs; Water regularly; do not overwater

Sun Exposure
Full Sun

Foliage
Deciduous
This plant is resistant to deer
Smooth

Foliage Color

Height
6-12 in. (15-30 cm)
12-18 in. (30-45 cm)
18-24 in. (45-60 cm)

Spacing
6-9 in. (15-22 cm)

Hardiness
USDA Zone 4a: to -34.4 °C (-30 °F)
USDA Zone 4b: to -31.6 °C (-25 °F)
USDA Zone 5a: to -28.8 °C (-20 °F)
USDA Zone 5b: to -26.1 °C (-15 °F)
USDA Zone 6a: to -23.3 °C (-10 °F)
USDA Zone 6b: to -20.5 °C (-5 °F)
USDA Zone 7a: to -17.7 °C (0 °F)
USDA Zone 7b: to -14.9 °C (5 °F)
USDA Zone 8a: to -12.2 °C (10 °F)
USDA Zone 8b: to -9.4 °C (15 °F)

Where to Grow

Danger
N/A

Bloom Color
Dark Blue
Blue-Violet

Bloom Characteristics
Flowers are good for drying and preserving

Bloom Size

Bloom Time
Late Spring/Early Summer

Other details

Soil pH requirements
6.1 to 6.5 (mildly acidic)
6.6 to 7.5 (neutral)
7.6 to 7.8 (mildly alkaline)

Patent Information
Non-patented

Propagation Methods
By dividing rhizomes, tubers, corms or bulbs (including offsets)

Seed Collecting
N/A: plant does not set seed, flowers are sterile, or plants will not come true from seed