Oenothera flava
Yellow evening primrose
(c) Jose Luis Leon de la Luz, some rights reserved (CC BY) · licence
Family: Onagraceae · Type: Herb · Native
Oenothera flava (Yellow evening primrose) is a native California herb in the Onagraceae family, recognized by stemless habit and winged seeds are key.
Yellow evening primrose is a California native perennial found in the northern Sierra Nevada Mountains, Modoc Plateau, and northern Sierra Nevada in sagebrush scrub and pinyon-juniper woodland at elevations of 900 to 1,600 meters. Flowering from May to July, this plant produces bright yellow flowers that fade to pale orange, with petals 10 to 30 millimeters long. Growing with a rosetted habit and essentially stemless, it develops a fleshy taproot and forms oblanceolate to oblong leaves 3 to 36 centimeters long with irregular pinnate lobes. Its leaves are somewhat fleshy with glandular and minute strigose hairs, creating a distinctive appearance in its dry, clay-based habitats. The elongated fruit is 10 to 40 millimeters long, narrowly ovate to elliptic, with small wings 2 to 6 millimeters wide.
Identification and appearance
Key characters: 8 sympatric species; stemless habit and winged seeds are key
Habitat and range
Habitat: Drying depressions, streambanks, generally clay soils, sagebrush scrub to pinyon/juniper woodland
Elevation: 900-1600 m
California counties: Lassen, Modoc, Plumas, Placer
Outside California: to southern Canada, Colorado, Mexico
Bloom period
Oenothera flava blooms May-Jul.
How to tell it apart
vs Camissoniopsis: Oenothera has a 4-lobed cross-shaped stigma; Camissoniopsis has a round stigma and four-angled fruits.; vs Clarkia: Oenothera has 4-lobed stigma and yellow flowers; Clarkia has round stigma and pink/purple flowers.; vs Rosa: Oenothera has 4 petals and capsule fruits; Rosa has 5+ petals and rose hips.; vs Convolvulus: Oenothera has separate petals; Convolvulus has fused trumpet-shaped flowers (morning glory family).; vs Taraxia: Oenothera has robust stems with 4-lobed stigma; Taraxia is stemless with flowers at ground level.
Frequently asked questions
Is Oenothera flava native to California?
Yes. Oenothera flava is native to California (recorded as native).
When does Oenothera flava bloom?
Oenothera flava blooms May-Jul.
Where in California does Oenothera flava grow?
Oenothera flava occurs in Lassen, Modoc, Plumas, Placer, at elevations of 900-1600 m.
What plant family does Oenothera flava belong to?
Oenothera flava is in the Onagraceae family, genus Oenothera.
What habitat does Oenothera flava grow in?
Oenothera flava grows in Drying depressions, streambanks, generally clay soils, sagebrush scrub to pinyon/juniper woodland.
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.