Allium triquetrum
Three cornered leek
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Family: Alliaceae · Type: Herb · Not Native
Allium triquetrum (Three cornered leek) is a non-native California herb in the Alliaceae family, recognized by distinctive 3-angled stem and pendulous white flowers.
Three cornered leek is a naturalized perennial found in northern California Coast, Klamath Ranges, and central California Coast bioregions in shady, somewhat disturbed places at elevations below 100 meters. Flowering from March to April, this plant produces delicate white flowers in bell-shaped clusters hanging from one-sided stems. Growing with distinctively sharp three-cornered stems 10 to 40 centimeters tall, it emerges from small ovoid bulbs with thin, yellowish-brown outer coats. Its leaves are 2 to 3 in number, flat and roughly equal in length to the stem, spreading from the base. This invasive plant has pendant flowers 10 to 18 millimeters long with lanceolate white perianth parts that create a graceful, nodding appearance.
Identification and appearance
Key characters: 26 sympatric species; distinctive 3-angled stem and pendulous white flowers are diagnostic
Habitat and range
Habitat: Locally common. Shady +- disturbed places
Elevation: < 100 m
California counties: Sacramento, Marin, San Francisco, Sonoma, San Bernardino, Riverside, Alameda, Del Norte, Humboldt, Mendocino, San Mateo, Santa Clara, Yolo, Tehama, Contra Costa, Napa, Trinity, San Luis Obispo, Monterey, San Joaquin, Tuolumne, Santa Cruz
Outside California: native to western Mediterranean
Bloom period
Allium triquetrum blooms Mar-Apr.
How to tell it apart
vs Triteleia: Allium smells like onion when crushed; triplet lily has no smell.; vs Agapanthus: Allium smells like onion; lily-of-the-Nile has no smell and much larger flowers.; vs Dipterostemon: Allium smells like onion when crushed; ookow has no onion smell.; vs Nothoscordum: Allium smells like onion when crushed; false garlic has no smell.; vs Tulbaghia: Allium has flowers in tight umbels; society garlic has flowers in loose open clusters.
Frequently asked questions
Is Allium triquetrum native to California?
No. Allium triquetrum is not native to California (recorded as not native).
When does Allium triquetrum bloom?
Allium triquetrum blooms Mar-Apr.
Where in California does Allium triquetrum grow?
Allium triquetrum occurs in Sacramento, Marin, San Francisco, Sonoma, San Bernardino, Riverside, Alameda, Del Norte and other counties, at elevations of < 100 m.
What plant family does Allium triquetrum belong to?
Allium triquetrum is in the Alliaceae family, genus Allium.
What habitat does Allium triquetrum grow in?
Allium triquetrum grows in Locally common. Shady +- disturbed places.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · Index of California Plant Names · CalPhotos
Last updated 2026-10-07
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.