Oenothera deltoides subsp. cognata
Photo: parent species Oenothera deltoides · no rights reserved · CC0
Family: Onagraceae · Type: Herb · Native
Oenothera deltoides subsp. cognata is a native California herb in the Onagraceae family.
Evening primrose is a California native perennial herb found in the San Joaquin Valley, La Panza Range, and western Mojave Desert in sandy grassland habitats at elevations below 700 meters. Flowering from March to May, this plant produces delicate white to pale yellow flowers with large petals 25 to 40 millimeters long. Growing with branched stems 20 to 60 centimeters tall that spread from the base, it develops spreading hairs approximately 2 millimeters long on its upper portions. Its leaves are variable, with upper leaves nearly entire to wavy-toothed and occasionally showing rare pinnate lobing. The plant's distinctive open branching and large pale flowers make it a notable feature of sandy desert and grassland environments.
Habitat and range
Habitat: Sandy soils, grassland
Elevation: < 700 m
California counties: Kern, San Joaquin, Kings, Merced, Fresno, San Luis Obispo, San Bernardino, Monterey, Stanislaus, Contra Costa, Santa Barbara, Lassen, Alameda, Sacramento, Los Angeles
Bloom period
Oenothera deltoides subsp. cognata blooms Mar-May.
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 deltoides subsp. cognata native to California?
Yes. Oenothera deltoides subsp. cognata is native to California (recorded as native).
When does Oenothera deltoides subsp. cognata bloom?
Oenothera deltoides subsp. cognata blooms Mar-May.
Where in California does Oenothera deltoides subsp. cognata grow?
Oenothera deltoides subsp. cognata occurs in Kern, San Joaquin, Kings, Merced, Fresno, San Luis Obispo, San Bernardino, Monterey and other counties, at elevations of < 700 m.
What plant family does Oenothera deltoides subsp. cognata belong to?
Oenothera deltoides subsp. cognata is in the Onagraceae family, genus Oenothera.
What habitat does Oenothera deltoides subsp. cognata grow in?
Oenothera deltoides subsp. cognata grows in Sandy soils, grassland.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · 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.