Wildflower (forb) · Asteraceae
Smooth blue aster
Symphyotrichum laeve · includes its varieties and subspecies
Smooth blue aster is recorded as native to 46 states and territories in Kew’s World Checklist of Vascular Plants and USDA PLANTS, and recorded in 875 counties of those states by USDA PLANTS.
Key facts · USDA PLANTS
Smooth blue aster at a glance
- Native in
- 875 counties, across 46 states and territories
- Estimated cold hardiness
- Zone 3a PLANTS minimum temperature −43°F
- Mature height
- 4 ft PLANTS mature height
- Light and water
- Full sun (shade-intolerant) Medium water use
Estimated cold hardiness: zone 3a. PLANTS gives a minimum temperature of −43°F; zone 3a winters bottom out at −40°F, the coldest half-zone that stays within that limit.
Smooth blue aster is recorded as native to 46 states and territories in Kew’s World Checklist of Vascular Plants and USDA PLANTS, and recorded in 875 counties of those states by USDA PLANTS.
Counties where it is native
The 15 counties with the most ZIP codes among the 875 where it is listed.
Native counties by state
- Alabama 13 counties
- Arkansas 11 counties
- California 1 county
- Colorado 18 counties
- Connecticut statewide record
- Delaware 1 county
- District of Columbia 1 county
- Florida 2 counties
- Georgia 3 counties
- Idaho 10 counties
- Illinois 57 counties
- Indiana 24 counties
- Iowa 28 counties
- Kansas 23 counties
- Kentucky 21 counties
- Louisiana 9 counties
- Maine 2 counties
- Maryland 2 counties
- Massachusetts 12 counties
- Michigan 64 counties
- Minnesota 61 counties
- Mississippi 7 counties
- Missouri 76 counties
- Montana 18 counties
- Nebraska 12 counties
- Nevada 2 counties
- New Hampshire 7 counties
- New Jersey 14 counties
- New Mexico 15 counties
- New York 35 counties
- North Carolina 11 counties
- North Dakota 39 counties
- Ohio 51 counties
- Pennsylvania 45 counties
- Rhode Island 2 counties
- South Carolina 4 counties
- South Dakota 18 counties
- Tennessee 15 counties
- Texas 5 counties
- Utah 3 counties
- Vermont 4 counties
- Virginia 42 counties
- Washington 6 counties
- West Virginia 15 counties
- Wisconsin 55 counties
- Wyoming 11 counties
Growing traits
Values from the PLANTS characteristics record of a variety (SYLAL3). “Not recorded” means PLANTS has no value; nothing here is estimated except the zone.
Growth
- Growth habit
- Forb/herb
- Duration
- Perennial
- Mature height
- 4 ft
- Growth rate
- Moderate
- Growth form
- Rhizomatous
- Shape
- Erect
- Lifespan
- Short
- Active growth period
- Spring and Summer
Light and water
- Shade tolerance
- Intolerant (full sun (shade-intolerant))
- Moisture use
- Medium water use
- Drought tolerance
- Medium
- Tolerance of waterlogged soil
- None
- Precipitation range
- 20 to 35 in per year
Soil
- Soil textures
- Coarse and medium
- pH range
- 5.8 to 7.8
- Lime (CaCO₃) tolerance
- Medium
- Salinity tolerance
- None
- Fertility requirement
- Low
- Minimum root depth
- 10 in
Climate
- Minimum temperature
- −43°F
- Estimated cold hardiness
- Zone 3a and warmer
- Minimum frost-free days
- 100
- Fire tolerance
- High
Flowers, leaves and fruit
- Flower color
- Purple
- Showy flowers
- Yes
- Bloom period
- Mid Summer
- Foliage color
- Green
- Showy in fall
- Yes
- Keeps leaves
- No
- Fruit color
- Brown
Other
- Toxicity
- None
- Nitrogen fixation
- None
- Nursery availability
- Contracting Only
- Family
- Asteraceae
- PLANTS symbol
- SYLA3
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
- Symphyotrichum laeve (PLANTS symbol SYLA3), including 3 varieties and 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