Psorothamnus schottii
Indigo-bush
Photo by Chez Brungraber
Family: Fabaceae · Type: Shrub · Native
Psorothamnus schottii (Indigo-bush) is a native California shrub in the Fabaceae family, recognized by simple leaves are diagnostic among sympatric species.
Indigo-bush is a California native shrub found in the southern desert region in gravelly to sandy slopes, benches, and washes at elevations below 600 meters. Flowering from March to May, this plant produces deep blue flowers with a yellow banner spot, clustered in open inflorescences with 5 to 20 blossoms. Growing as a compact shrub less than 2 meters tall with green stems that become gray-strigose with age, it develops a distinctive appearance. Its simple leaves are linear, 1 to 3 centimeters long, densely puberulent and gland-dotted, remaining persistent throughout the growing season. The fruit is exserted, 7 to 10 millimeters long, with widely spaced large glands.
Identification and appearance
Key characters: 5 sympatric species; simple leaves are diagnostic among sympatric species
Habitat and range
Habitat: Gravelly to sandy slopes, benches, washes
Elevation: < 600 m
California counties: Riverside, Imperial, San Diego, Kern, San Bernardino
Outside California: Arizona, northwestern Mexico, Baja California
Bloom period
Psorothamnus schottii blooms Mar-May.
How to tell it apart
vs Psorodendron: Psorothamnus has gland-dotted surfaces and indigo-purple flowers; Psorodendron has smooth surfaces and yellow flowers.; vs Astragalus: Psorothamnus has gland-dotted surfaces and single-seeded pods; Astragalus has smooth surfaces and multi-seeded inflated pods.; vs Dalea: Psorothamnus has petals arising from flower base; Dalea has petals arising from a fused stamen column.; vs Condea: Psorothamnus has pea-shaped flowers; Condea has two-lipped tubular flowers (mint family).; vs Scutellaria: Psorothamnus has pea-shaped flowers; Scutellaria has hooded two-lipped flowers (mint family).
Frequently asked questions
Is Psorothamnus schottii native to California?
Yes. Psorothamnus schottii is native to California (recorded as native).
When does Psorothamnus schottii bloom?
Psorothamnus schottii blooms Mar-May.
Where in California does Psorothamnus schottii grow?
Psorothamnus schottii occurs in Riverside, Imperial, San Diego, Kern, San Bernardino, at elevations of < 600 m.
What plant family does Psorothamnus schottii belong to?
Psorothamnus schottii is in the Fabaceae family, genus Psorothamnus.
What habitat does Psorothamnus schottii grow in?
Psorothamnus schottii grows in Gravelly to sandy slopes, benches, washes.
Related species
Other California species in the same genus, family, or bioregion.
- Psorothamnus sp. — Indigo-bush
- Psorothamnus spinosus — Smoke tree
- Psorothamnus arborescens — Mojave indigo-bush
- Psorothamnus arborescens var. arborescens — Mojave indigo bush
- Psorothamnus arborescens var. californicus — California indigo bush
- Psorothamnus arborescens var. minutifolius — Johnson's indigobush
- Robinia neomexicana — New mexico locust
- Robinia pseudoacacia — Black locust
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.