Allium howellii var. sanbenitense
San benito onion, San Benito onion, San Benito onion
Photo: parent species Allium howellii · (c) paulexcoff, some rights reserved (CC BY-SA) · licence
Family: Alliaceae · Type: Herb · Native
Conservation status: CNPS 1B.3
Allium howellii var. sanbenitense (San benito onion) is a native California herb in the Alliaceae family, recognized by tall stature, large flower clusters, and prominently exserted stamens.
San benito onion is a rare (CNPS 1B.3) California native perennial found in southern central Coast Ranges in San Benito and Fresno counties, occurring in grassy openings within chaparral at elevations of 300 to 1,000 meters. Flowering from April to May, this plant produces white to pale pink flowers in dense clusters containing 50 to 90 blooms, with stamens extending 2 to 4 millimeters beyond the perianth. Growing with stout stems 25 to 60 centimeters tall, it emerges as a robust and distinctive onion species. Its leaves (though not detailed in source data) are characteristic of the Allium genus, likely linear and grass-like. The plant's white or green ovary crests and substantial flower clusters make it a notable endemic to its limited habitat range.
Identification and appearance
Key characters: 16 sympatric species; distinguished by tall stature, large flower clusters, and prominently exserted stamens
Habitat and range
Habitat: Uncommon. Grassy openings in chaparral, vertic clay
Elevation: 300-1000 m
Bloom period
Allium howellii var. sanbenitense blooms Apr-May.
Conservation status
CNPS 1B.3
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 howellii var. sanbenitense native to California?
Yes. Allium howellii var. sanbenitense is native to California (recorded as native).
When does Allium howellii var. sanbenitense bloom?
Allium howellii var. sanbenitense blooms Apr-May.
What plant family does Allium howellii var. sanbenitense belong to?
Allium howellii var. sanbenitense is in the Alliaceae family, genus Allium.
Is Allium howellii var. sanbenitense rare or endangered?
Allium howellii var. sanbenitense carries California Rare Plant Rank 1B.3, state rank S3.
What habitat does Allium howellii var. sanbenitense grow in?
Allium howellii var. sanbenitense grows in Uncommon. Grassy openings in chaparral, vertic clay.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · CNPS Rare Plant Inventory · Index of California Plant Names · CalPhotos · CDFW CNDDB
Last updated 2026-10-08
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.