Shrub · Fabaceae
False indigo bush
Amorpha fruticosa
False indigo bush is recorded as native to 20 states and territories in Kew’s World Checklist of Vascular Plants and USDA PLANTS, and recorded in 534 counties of those states by USDA PLANTS.
Key facts · USDA PLANTS
False indigo bush at a glance
- Native in
- 534 counties, across 20 states and territories
- Estimated cold hardiness
- Zone 3b PLANTS minimum temperature −38°F
- Mature height
- 15 ft PLANTS mature height
- Light and water
- Full sun (shade-intolerant) Low water use
Estimated cold hardiness: zone 3b. PLANTS gives a minimum temperature of −38°F; zone 3b winters bottom out at −35°F, the coldest half-zone that stays within that limit.
False indigo bush is recorded as native to 20 states and territories in Kew’s World Checklist of Vascular Plants and USDA PLANTS, and recorded in 534 counties of those states by USDA PLANTS.
Counties where it is native
The 15 counties with the most ZIP codes among the 534 where it is listed.
Native counties by state
- Alabama 41 counties
- Arizona 12 counties
- California 5 counties
- Colorado 14 counties
- Florida 53 counties
- Idaho 11 counties
- Illinois 81 counties
- Kentucky 49 counties
- Minnesota 55 counties
- New Mexico 14 counties
- North Dakota 15 counties
- Oregon 11 counties
- Pennsylvania 16 counties
- Tennessee 38 counties
- Texas 74 counties
- Utah 4 counties
- Vermont 3 counties
- Washington 14 counties
- Wisconsin 20 counties
- Wyoming 4 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
- Shrub
- Duration
- Perennial
- Mature height
- 15 ft
- Growth rate
- Slow
- Growth form
- Multiple Stem
- Shape
- Climbing
- Lifespan
- Moderate
- Active growth period
- Spring and Summer
Light and water
- Shade tolerance
- Intolerant (full sun (shade-intolerant))
- Moisture use
- Low water use
- Drought tolerance
- Medium
- Tolerance of waterlogged soil
- None
- Precipitation range
- 10 to 65 in per year
Soil
- Soil textures
- Coarse and medium
- pH range
- 5 to 8.5
- Lime (CaCO₃) tolerance
- Medium
- Salinity tolerance
- Low
- Fertility requirement
- Low
- Minimum root depth
- 24 in
Climate
- Minimum temperature
- −38°F
- Estimated cold hardiness
- Zone 3b and warmer
- Minimum frost-free days
- 100
- Fire tolerance
- Low
Flowers, leaves and fruit
- Flower color
- Purple
- Showy flowers
- No
- Bloom period
- Late Spring
- Foliage color
- Green
- Showy in fall
- No
- Keeps leaves
- No
- Fruit color
- Brown
Other
- Toxicity
- Slight
- Nitrogen fixation
- Medium
- Nursery availability
- Routinely Available
- Family
- Fabaceae
- PLANTS symbol
- AMFR
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
- Amorpha fruticosa (PLANTS symbol AMFR).
- 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