Wildflower (forb) · Acanthaceae
Fringeleaf wild petunia
Ruellia humilis
Fringeleaf wild petunia is recorded as native to 22 states and territories in Kew’s World Checklist of Vascular Plants and USDA PLANTS, and recorded in 623 counties of those states by USDA PLANTS.
Key facts · USDA PLANTS
Fringeleaf wild petunia at a glance
- Native in
- 623 counties, across 22 states and territories
- Estimated cold hardiness
- Zone 4a PLANTS minimum temperature −33°F
- Mature height
- 2.6 ft PLANTS mature height
- Light and water
- Tolerates shade Low water use
Estimated cold hardiness: zone 4a. PLANTS gives a minimum temperature of −33°F; zone 4a winters bottom out at −30°F, the coldest half-zone that stays within that limit.
Fringeleaf wild petunia is recorded as native to 22 states and territories in Kew’s World Checklist of Vascular Plants and USDA PLANTS, and recorded in 623 counties of those states by USDA PLANTS.
Counties where it is native
The 15 counties with the most ZIP codes among the 623 where it is listed.
Native counties by state
- Alabama 4 counties
- Arkansas 54 counties
- Illinois 89 counties
- Indiana 33 counties
- Iowa 10 counties
- Kansas 58 counties
- Kentucky 38 counties
- Louisiana 38 counties
- Maryland 2 counties
- Michigan 3 counties
- Mississippi 17 counties
- Missouri 100 counties
- Nebraska 7 counties
- North Carolina 3 counties
- Ohio 24 counties
- Oklahoma 39 counties
- Pennsylvania 1 county
- Tennessee 26 counties
- Texas 61 counties
- Virginia 9 counties
- West Virginia 2 counties
- Wisconsin 5 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
- Perennial
- Mature height
- 2.6 ft
- Growth rate
- Moderate
- Growth form
- Single Stem
- Shape
- Erect
- Lifespan
- Short
- Active growth period
- Summer
Light and water
- Shade tolerance
- Tolerant (tolerates shade)
- Moisture use
- Low water use
- Drought tolerance
- Medium
- Tolerance of waterlogged soil
- None
- Precipitation range
- 20 to 55 in per year
Soil
- Soil textures
- Coarse, medium and fine
- pH range
- 4.5 to 7.5
- Lime (CaCO₃) tolerance
- Low
- Salinity tolerance
- None
- Fertility requirement
- Low
- Minimum root depth
- 4 in
Climate
- Minimum temperature
- −33°F
- Estimated cold hardiness
- Zone 4a and warmer
- Minimum frost-free days
- 160
- Fire tolerance
- None
Flowers, leaves and fruit
- Flower color
- Purple
- Showy flowers
- Yes
- Bloom period
- Summer
- Foliage color
- Green
- Showy in fall
- No
- Keeps leaves
- No
- Fruit color
- Yellow
Other
- Toxicity
- None
- Nitrogen fixation
- None
- Nursery availability
- No Known Source
- Family
- Acanthaceae
- PLANTS symbol
- RUHU
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
- Ruellia humilis (PLANTS symbol RUHU).
- 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