Wildflower (forb) · Amaranthaceae

Roughfruit amaranth

Amaranthus tuberculatus

Roughfruit amaranth is recorded as native to 24 states and territories in Kew’s World Checklist of Vascular Plants and USDA PLANTS, and recorded in 727 counties of those states by USDA PLANTS.

Recorded native ranges can include long-established populations that spread from gardens; check your state’s native plant society list for local guidance. How native status is decided.

Key facts · USDA PLANTS

Roughfruit amaranth at a glance

Native in: 727 counties, across 24 states and territories
Estimated cold hardiness: Zone 4a PLANTS minimum temperature −33°F
Mature height: 6.6 ft PLANTS mature height
Light and water: Full sun (shade-intolerant) High 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.

Counties where it is native

The 15 counties with the most ZIP codes among the 727 where it is listed.

Native counties by state

Arkansas 34 counties
Connecticut statewide record
Illinois 80 counties
Indiana 53 counties
Iowa 34 counties
Kansas 83 counties
Kentucky 15 counties
Louisiana 38 counties
Maine 2 counties
Massachusetts 7 counties
Michigan 25 counties
Minnesota 41 counties
Mississippi 6 counties
Missouri 63 counties
Nebraska 42 counties
New York 13 counties
North Dakota 11 counties
Ohio 52 counties
Oklahoma 28 counties
South Dakota 14 counties
Tennessee 14 counties
Texas 29 counties
Vermont 3 counties
Wisconsin 40 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: Annual
Mature height: 6.6 ft
Growth rate: Rapid
Growth form: Single Stem
Shape: Erect
Lifespan: Not recorded
Active growth period: Spring

Light and water

Shade tolerance: Intolerant (full sun (shade-intolerant))
Moisture use: High water use
Drought tolerance: None
Tolerance of waterlogged soil: High
Precipitation range: 15 to 60 in per year

Soil

Soil textures: Medium and fine
pH range: 5 to 8
Lime (CaCO₃) tolerance: Medium
Salinity tolerance: None
Fertility requirement: Low
Minimum root depth: 12 in

Climate

Minimum temperature: −33°F
Estimated cold hardiness: Zone 4a and warmer
Minimum frost-free days: 120
Fire tolerance: None

Flowers, leaves and fruit

Flower color: Green
Showy flowers: No
Bloom period: Summer
Foliage color: Green
Showy in fall: No
Keeps leaves: No
Fruit color: Black

Other

Toxicity: None
Nitrogen fixation: None
Nursery availability: No Known Source
Family: Amaranthaceae
PLANTS symbol: AMTU

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: Amaranthus tuberculatus (PLANTS symbol AMTU).
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

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