About

Allium canadense is a bulbous perennial native to North America, reaching heights of up to 45 cm. This plant develops grass-like clumps and produces rounded clusters of star-shaped blooms in shades of pink or white, arranged in umbels. The flowers may appear alone or in combination with bulbils and typically emerge from late spring through summer. It is well-suited for casual garden settings.

About the genus

Allium consists of bulbous herbaceous perennials characterized by a pronounced onion or garlic aroma. They feature linear, strap-like, or cylindrical leaves that arise from the base. The flowers, which can be star-shaped or bell-shaped, are arranged in an umbel atop a stem that lacks leaves.

Growing conditions

Sunlight

Full sun

Soil type

Chalk, Loam, Sand

Soil pH

Acid, Alkaline, Neutral

Soil moisture

Well-drained

Aspect

South-facing, West-facing

Exposure

Exposed, Sheltered

UK hardiness

H6

Plant details

Plant type

Bulbs

Habit

Clump forming

Foliage

Deciduous

Height

0.1-0.5 metres

Spread

0.1-0.5 metres

Time to full height

1-2 years

Suggested uses

City and courtyard gardens, Coastal, Cottage and informal garden, Gravel garden, Patio and container plants, Wildlife gardens

Fragrance

Foliage

Toxicity

TOXIC to pets - see the HTA guide to potentially harmful plants for further information and useful contact numbers

Care notes

Cultivation

Grow in full sun and fertile well-drained soil. It is best to grow in containers where garden soil is heavy clay and prone to saturation over winter. Increases rapidly and may become a nuisance, so best naturalised in a wild garden or meadow. See allium cultivation

Pruning

No pruning required, other than to remove old flowered stems and foliage

Propagation

Propagate by offsets which can be carefully detached by lifting the bulb after flowering has finished. See bulb propagation

Pest resistance

May be susceptible to allium leaf miner and onion fly

Disease resistance

May be susceptible to onion white rot, and onion downy mildew