Allium validum
A tall, bulb-forming onion-family perennial native to high-elevation, wet meadows of western North America, with a 50–100 cm stem bearing an umbel of pink to white flowers on a leafless stalk, and onion-scented edible bulbs and leaves used for flavoring.
Common Names
Swamp Onion, Pacific Onion, Tall Swamp Onion, Pacific Mountain Onion
Summary
Native to western North America, including British Columbia, California, Idaho, Nevada, Oregon, and Washington, this perennial forms clusters from a bulb and grows in swampy meadows at 1,200–3,400 m. A stem 50–100 cm tall bears 3–6 flat or keeled leaves and an umbel of 15–40 flowers; perianth parts are rose to white, erect and narrowly lanceolate, with stamens extending beyond the petals. Edible parts include the bulb, leaves, and flowers (bulb as flavoring in soups and stews; leaves raw or cooked; flowers garnish); pollinators visit; the whole plant reputedly repels insects and moles, and the juice serves as a moth repellent. Bloom time typically June–August.
Cultivation emphasizes a sunny position in light, well-drained soil with ample moisture during the growing season; tolerates wetter soils than many onions but dislikes damp, cold winters without snow cover. Propagation occurs by seed (spring in a cold frame) or by division in spring; bulbs should be planted deeply. Hardiness ranges from USDA zones 7–10, with deer rarely browsed. Uses include edible bulb, leaves, and flowers; bulb flavoring in soups and stews; leaves eaten raw or cooked; flowers used as a garnish; nectar attracts pollinators; juice acts as a moth repellent; whole plant reputed to repel insects and moles; potential as a rain garden plant.
Lifecycle
Perennial
Height
1 ft 8 in-3 ft 4 in
Spread
1-3 feet
Hardiness Zones
Zones 7-10
Sunlight Requirements
Ideally full sun. Tolerates partial shade
Soil Type
Light to loamy, well-drained soil that is damp but not waterlogged.
Soil Drainage
Well-drained soil
Soil pH
No single ideal pH, 6.2-8.0, tolerates acidic to alkaline soils
Bloom Color
Pink to white
Bloom Time
Summer
Foliage Color
Green
Fall Foliage Color
Green
Leaf Lifecycle
Deciduous
Growth Rate
Moderate
Seasons of Interest
Spring and Summer
Propagation Methods
Seeds, Division, Bulblets
Attracts Wildlife
Attracts moths, bees, flies, small solitary wasps, and beetles
Taxonomy
- Taxonomic Rank
- Species
- Author
- S.Watson
- Publication
- Botany [Fortieth Parallel] : 350 (1871)
Superior Taxa
- Kingdom
- Plantae
- Subkingdom
- Pteridobiotina
- Phylum
- Angiosperms
- Order
- Asparagales
- Family
- Amaryllidaceae
- Genus
- Allium