Eulobus californicus
California primrose
Photo by Chez Brungraber
Family: Onagraceae · Type: Herb · Native
Eulobus californicus (California primrose) is a native California herb in the Onagraceae family, recognized by Genus endemic to southwestern North America; specialized fruit morphology distinguishes it from other Onagraceae.
California primrose is a native annual herb found in the Sonoma Coast Ranges, San Joaquin Valley, South Coast Ranges, southwestern California, and desert regions in open places within coastal-sage scrub, chaparral, and desert scrub at elevations below 1,300 meters. Flowering from April to June, this plant produces pale yellow to yellow flowers with petals 6 to 14 millimeters long. Growing with erect, straight stems 20 to 180 centimeters tall that are slender and slightly glaucous or green, it develops a well-formed basal rosette. Its leaves are narrowly elliptic, dramatically pinnately lobed with irregular sharp edges, becoming much smaller toward the stem's upper portions. The fruit is a distinctive cylindrical pod that dries to a four-angled shape, reaching 45 to 110 millimeters long and reflexed from the stem.
Identification and appearance
Key characters: Genus endemic to southwestern North America; specialized fruit morphology distinguishes it from other Onagraceae
Habitat and range
Habitat: Open places in coastal-sage scrub, chaparral, desert scrub
Elevation: < 1300 m
California counties: San Bernardino, Los Angeles, Ventura, Riverside, Kern, Imperial, San Diego, Santa Barbara, San Luis Obispo, Fresno, San Benito, Kings, Orange, Mendocino, Inyo, Mono, Monterey
Outside California: southern and western Arizona, northwestern Mexico
Bloom period
Eulobus californicus blooms Apr-Jun.
How to tell it apart
vs Camissoniopsis: Eulobus has wand-like stems with red-flecked petals; Camissoniopsis has four-angled fruits and plain petals.; vs Camissonia: Eulobus has red flecks at petal bases on wand-like stems; Camissonia has plain petals.; vs Chylismia: Eulobus has elegant wand stems with red-flecked petals; Chylismia has basal dandelion-like leaves.; vs Oenothera: Eulobus has slender wands with red-flecked petals; Oenothera is robust with 4-lobed stigma.; vs Eschscholzia: Eulobus has red-flecked 4-petaled flowers; Eschscholzia has dissected leaves and poppy-like flowers.
Frequently asked questions
Is Eulobus californicus native to California?
Yes. Eulobus californicus is native to California (recorded as native).
When does Eulobus californicus bloom?
Eulobus californicus blooms Apr-Jun.
Where in California does Eulobus californicus grow?
Eulobus californicus occurs in San Bernardino, Los Angeles, Ventura, Riverside, Kern, Imperial, San Diego, Santa Barbara and other counties, at elevations of < 1300 m.
What plant family does Eulobus californicus belong to?
Eulobus californicus is in the Onagraceae family, genus Eulobus.
What habitat does Eulobus californicus grow in?
Eulobus californicus grows in Open places in coastal-sage scrub, chaparral, desert scrub.
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.