Allium bolanderi var. bolanderi
Bolander's onion
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Family: Alliaceae · Type: Herb · Native
Allium bolanderi var. bolanderi (Bolander's onion) is a native California herb in the Alliaceae family, recognized by oblique bulb shape and serrated bulb coat edges are key.
Bolander's onion is a California native perennial found in northwestern California, the Cascade Range, and southeastern San Francisco Bay Area in rocky clay habitats including serpentine areas at elevations below 1,000 meters. Flowering from May to August, this plant produces white to pale pink flowers with narrowly ovate perianth parts 8 to 12 millimeters long. Growing with an oblique-ovoid bulb 7 to 12 millimeters in size, it develops a distinctive outer bulb coating that breaks apart with serrate (saw-toothed) edges. Its leaves emerge from the distinctive bulb, typically slender and characteristic of the onion family. The plant thrives in challenging clay soils, particularly serpentine landscapes that few other species can tolerate.
Identification and appearance
Key characters: 26 sympatric species, oblique bulb shape and serrated bulb coat edges are key
Habitat and range
Habitat: Uncommon. Rocky clays including serpentine
Elevation: < 1000 m
California counties: Humboldt, Lake, Mendocino, Shasta, Siskiyou, Tehama, Trinity, Napa, Glenn
Outside California: southwestern Oregon
Bloom period
Allium bolanderi var. bolanderi blooms May-Aug.
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 bolanderi var. bolanderi native to California?
Yes. Allium bolanderi var. bolanderi is native to California (recorded as native).
When does Allium bolanderi var. bolanderi bloom?
Allium bolanderi var. bolanderi blooms May-Aug.
Where in California does Allium bolanderi var. bolanderi grow?
Allium bolanderi var. bolanderi occurs in Humboldt, Lake, Mendocino, Shasta, Siskiyou, Tehama, Trinity, Napa and other counties, at elevations of < 1000 m.
What plant family does Allium bolanderi var. bolanderi belong to?
Allium bolanderi var. bolanderi is in the Alliaceae family, genus Allium.
What habitat does Allium bolanderi var. bolanderi grow in?
Allium bolanderi var. bolanderi grows in Uncommon. Rocky clays including serpentine.
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.