Wildflower (forb) · Scrophulariaceae
Canadian lousewort
Pedicularis canadensis · includes its varieties and subspecies
Canadian lousewort is recorded as native to 38 states and territories in Kew’s World Checklist of Vascular Plants and USDA PLANTS, and recorded in 1,115 counties of those states by USDA PLANTS.
Key facts · USDA PLANTS
Canadian lousewort at a glance
- Native in
- 1,115 counties, across 38 states and territories
- Estimated cold hardiness
- Zone 3a PLANTS minimum temperature −43°F
- Mature height
- 1.3 ft PLANTS mature height
- Light and water
- Tolerates shade 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.
Canadian lousewort is recorded as native to 38 states and territories in Kew’s World Checklist of Vascular Plants and USDA PLANTS, and recorded in 1,115 counties of those states by USDA PLANTS.
Counties where it is native
The 15 counties with the most ZIP codes among the 1,115 where it is listed.
Native counties by state
- Alabama 13 counties
- Arkansas 52 counties
- Colorado 8 counties
- Connecticut statewide record
- Delaware 1 county
- District of Columbia 1 county
- Florida 5 counties
- Georgia 27 counties
- Illinois 60 counties
- Indiana 48 counties
- Iowa 7 counties
- Kansas 17 counties
- Kentucky 51 counties
- Louisiana 29 counties
- Maine 14 counties
- Massachusetts 14 counties
- Michigan 67 counties
- Minnesota 70 counties
- Mississippi 21 counties
- Missouri 94 counties
- Nebraska 5 counties
- New Hampshire 7 counties
- New Mexico 5 counties
- New York 45 counties
- North Carolina 48 counties
- North Dakota 3 counties
- Ohio 65 counties
- Oklahoma 12 counties
- Pennsylvania 60 counties
- Rhode Island 3 counties
- South Carolina 15 counties
- South Dakota 9 counties
- Tennessee 55 counties
- Texas 19 counties
- Vermont 6 counties
- Virginia 61 counties
- West Virginia 35 counties
- Wisconsin 63 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, Subshrub
- Duration
- Perennial
- Mature height
- 1.3 ft
- Growth rate
- Moderate
- Growth form
- Single Stem
- Shape
- Erect
- Lifespan
- Moderate
- Active growth period
- Spring and Summer
Light and water
- Shade tolerance
- Tolerant (tolerates shade)
- Moisture use
- Medium water use
- Drought tolerance
- Low
- Tolerance of waterlogged soil
- None
- Precipitation range
- 34 to 60 in per year
Soil
- Soil textures
- Medium and fine
- pH range
- 4 to 7
- Lime (CaCO₃) tolerance
- Medium
- Salinity tolerance
- None
- Fertility requirement
- Medium
- Minimum root depth
- 6 in
Climate
- Minimum temperature
- −43°F
- Estimated cold hardiness
- Zone 3a and warmer
- Minimum frost-free days
- 120
- Fire tolerance
- Medium
Flowers, leaves and fruit
- Flower color
- Yellow
- Showy flowers
- Yes
- Bloom period
- Late Spring
- Foliage color
- Gray-Green
- Showy in fall
- No
- Keeps leaves
- No
- Fruit color
- Black
Other
- Toxicity
- None
- Nitrogen fixation
- None
- Nursery availability
- No Known Source
- Family
- Scrophulariaceae
- PLANTS symbol
- PECA
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
- Pedicularis canadensis (PLANTS symbol PECA), 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