Wildflower (forb) · Amaranthaceae

California amaranth

Amaranthus californicus

California amaranth is recorded as native to 9 states and territories in Kew’s World Checklist of Vascular Plants and USDA PLANTS, and recorded in 61 counties of those states by USDA PLANTS.

Recorded native ranges can include long-established populations that spread from gardens; check your state’s native plant society list for local guidance. How native status is decided.

Key facts · USDA PLANTS

California amaranth at a glance

Native in: 61 counties, across 9 states and territories
Estimated cold hardiness: Zone 7a PLANTS minimum temperature −3°F
Mature height: 1 ft PLANTS mature height
Light and water: Full sun (shade-intolerant) Medium water use

Estimated cold hardiness: zone 7a. PLANTS gives a minimum temperature of −3°F; zone 7a winters bottom out at 0°F, the coldest half-zone that stays within that limit.

Counties where it is native

The 15 counties with the most ZIP codes among the 61 where it is listed.

Native counties by state

California 30 counties
Idaho 4 counties
Montana 2 counties
Nevada 7 counties
Oregon 7 counties
Texas 3 counties
Utah 1 county
Washington 5 counties
Wyoming 2 counties

Growing traits

Values from the PLANTS characteristics record. “Not recorded” means PLANTS has no value; nothing here is estimated except the zone.

Growth

Growth habit: Forb/herb
Duration: Annual
Mature height: 1 ft
Growth rate: Moderate
Growth form: Multiple Stem
Shape: Prostrate
Lifespan: Not recorded
Active growth period: Spring, Summer, Fall

Light and water

Shade tolerance: Intolerant (full sun (shade-intolerant))
Moisture use: Medium water use
Drought tolerance: Low
Tolerance of waterlogged soil: Low
Precipitation range: 14 to 24 in per year

Soil

Soil textures: Medium and fine
pH range: 5.5 to 7.5
Lime (CaCO₃) tolerance: Medium
Salinity tolerance: None
Fertility requirement: Medium
Minimum root depth: 4 in

Climate

Minimum temperature: −3°F
Estimated cold hardiness: Zone 7a and warmer
Minimum frost-free days: 175
Fire tolerance: None

Flowers, leaves and fruit

Flower color: Red
Showy flowers: No
Bloom period: Summer
Foliage color: Green
Showy in fall: Yes
Keeps leaves: No
Fruit color: Red

Other

Toxicity: None
Nitrogen fixation: None
Nursery availability: No Known Source
Family: Amaranthaceae
PLANTS symbol: AMCA

Source & data date

Source: USDA NRCS PLANTS Database: county distribution records, native status and plant characteristics. CC0 (public domain dedication, per the data.gov catalog record).; Kew’s World Checklist of Vascular Plants (WCVP): native or introduced status by state. CC BY 3.0.; USGS US-RIIS (ver. 2.0): species listed as introduced are excluded. CC0.
Citation: USDA, NRCS. 2026. The PLANTS Database (https://plants.usda.gov, 11/04/2026). National Plant Data Team, Greensboro, NC USA.; Govaerts R. (ed.) (2026). WCVP: World Checklist of Vascular Plants. Facilitated by the Royal Botanic Gardens, Kew. Data file dated 2026-06-04, http://sftp.kew.org/pub/data-repositories/WCVP/ (retrieved 2026-11-04). Paper: Govaerts R. et al. (2021) The World Checklist of Vascular Plants, a continuously updated resource for exploring global plant diversity. Scientific Data 8, 215.
Data date: Retrieved from PLANTS on November 4, 2026; WCVP data file dated June 4, 2026.
Scope: Amaranthus californicus (PLANTS symbol AMCA).
Method: A species is listed when it is recorded as native to the state in Kew’s World Checklist of Vascular Plants and USDA PLANTS, and recorded in the county by USDA PLANTS. Species PLANTS labels both native and introduced are listed separately. Full method · All sources

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