Wildflower (forb) · Asteraceae
Bigelow's tansyaster
Machaeranthera bigelovii · includes its varieties and subspecies
Bigelow's tansyaster is recorded as native to 5 states and territories in Kew’s World Checklist of Vascular Plants and USDA PLANTS, and recorded in 54 counties of those states by USDA PLANTS.
Key facts · USDA PLANTS
Bigelow's tansyaster at a glance
- Native in
- 54 counties, across 5 states and territories
- Estimated cold hardiness
- Zone 10b PLANTS minimum temperature 32°F
- Mature height
- 4 ft PLANTS mature height
- Light and water
- Full sun (shade-intolerant) Low water use
Estimated cold hardiness: zone 10b. PLANTS gives a minimum temperature of 32°F; zone 10b winters bottom out at 35°F, the coldest half-zone that stays within that limit.
Bigelow's tansyaster is recorded as native to 5 states and territories in Kew’s World Checklist of Vascular Plants and USDA PLANTS, and recorded in 54 counties of those states by USDA PLANTS.
Counties where it is native
The 15 counties with the most ZIP codes among the 54 where it is listed.
Native counties by state
- Arizona 11 counties
- Colorado 22 counties
- New Mexico 15 counties
- Utah 5 counties
- Wyoming 1 county
Growing traits
Values from the PLANTS characteristics record of a variety (MABIB). “Not recorded” means PLANTS has no value; nothing here is estimated except the zone.
Growth
- Growth habit
- Forb/herb
- Duration
- Biennial, Perennial
- Mature height
- 4 ft
- Growth rate
- Rapid
- Growth form
- Multiple Stem
- Shape
- Erect
- Lifespan
- Short
- Active growth period
- Spring and Summer
Light and water
- Shade tolerance
- Intolerant (full sun (shade-intolerant))
- Moisture use
- Low water use
- Drought tolerance
- High
- Tolerance of waterlogged soil
- None
- Precipitation range
- 6 to 18 in per year
Soil
- Soil textures
- Coarse, medium and fine
- pH range
- 6 to 8.5
- Lime (CaCO₃) tolerance
- High
- Salinity tolerance
- None
- Fertility requirement
- Low
- Minimum root depth
- 6 in
Climate
- Minimum temperature
- 32°F
- Estimated cold hardiness
- Zone 10b and warmer
- Minimum frost-free days
- 160
- Fire tolerance
- Not recorded
Flowers, leaves and fruit
- Flower color
- Purple
- Showy flowers
- Yes
- Bloom period
- Fall
- Foliage color
- Green
- Showy in fall
- Yes
- Keeps leaves
- No
- Fruit color
- White
Other
- Toxicity
- None
- Nitrogen fixation
- None
- Nursery availability
- Routinely Available
- Family
- Asteraceae
- PLANTS symbol
- MABI
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
- Machaeranthera bigelovii (PLANTS symbol MABI), including 1 variety or subspecies folded into the species.
- 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