Overview
Allium crenulatum is a clump forming bulbs in the genus Allium, part of the Amaryllidaceae family, with deciduous foliage. Allium crenulatum grows best in full sun, and tolerates most soils and any pH. Its UK hardiness is rated H6. Suggested uses include city and courtyard gardens, cottage and informal garden, gravel garden, patio and container plants, wildlife gardens, cut flowers and flower borders and beds.
About
Allium crenulatum, common name Olympic onion, is a plant species native to Oregon, Washington, and British Columbia. It grows in the Cascades, the Coast Ranges, the Olympic Mountains, the Wenatchee Mountains, and the mountains on Vancouver Island. There is one report from Alabama, but this needs verification. The species grows on talus slopes and in alpine tundra at elevations of 600–2500 m. In the garden it prefers full sun and most soil types. In UK gardens it is very hardy across most of the UK (RHS H6). Suggested uses include city and courtyard gardens, cottage and informal garden, gravel garden, patio and container plants, wildlife gardens, cut flowers and flower borders and beds. It tolerates soil of any pH, well-drained conditions and south-facing, west-facing and east-facing aspects. Plant bulbs in autumn in fertile, well-drained soil in full sun. Most are fully hardy and undemanding. Allow foliage to die back naturally.
Wikipedia contributors, CC BY-SA 4.0 — Allium crenulatum
About the genus
Allium is a large genus of monocotyledonous flowering plants with 1112 accepted species, making Allium the largest genus in the family Amaryllidaceae and among the largest plant genera in the world. Many of the species are edible, and some have a long history of cultivation and human consumption such as the onion, garlic, scallions, shallots, leeks, and chives.
Wikipedia contributors, "Allium", CC BY-SA 4.0 — Allium
Growing conditions
Best soil and position for Allium
- Sunlight
- Full sun
- Soil type
- Chalk, Clay, Loam, Sand
- Soil pH
- Acid, Alkaline, Neutral
- Soil moisture
- Well-drained
- Aspect
- South-facing, West-facing, East-facing
- Exposure
- Exposed, Sheltered
- UK hardiness
- H6
Plant details
Allium crenulatum size, habit and characteristics
- Plant type
- Bulbs
- Habit
- Clump forming
- Foliage
- Deciduous
- Suggested uses
- City and courtyard gardens, Cottage and informal garden, Gravel garden, Patio and container plants, Wildlife gardens, Cut flowers, Flower borders and beds
Care notes
Pruning and caring for Allium crenulatum
- Propagation
- Offsets, Seed
- Pest resistance
- Allium leaf miner, Onion fly
- Disease resistance
- Onion white rot, Onion downy mildew
Frequently asked questions
Where is the best place to plant Allium crenulatum?
Allium crenulatum prefers full sun. It suits exposed and sheltered positions.
What soil does Allium crenulatum need?
Allium crenulatum is adaptable and grows happily in most soil types, including chalk, clay, loam and sand. It is happy in soil of any pH. Aim for soil that stays well-drained.
Is Allium crenulatum hardy in the UK?
Allium crenulatum has an RHS hardiness rating of H6, meaning it is very hardy, tolerating -20 to -15°C across most of the UK.
How do I propagate Allium crenulatum?
Offsets, Seed.
More in the Allium genus
- Allium 'Judith'
- Allium 'Summer Beauty'
- Allium cepa 'Goldito'
- Allium christophii (albopilosum)Star of Persia
- Allium hookeri 'Zorami'Hooker Chives
- Allium phanerantherumconspicuous-anthered garlic
- Allium 'Millenium'
- Allium schmitzii