// SPECIES PROFILE · PERENNIAL · NATIVE

Stiff cowbane

Oxypolis rigidior

Stiff cowbane (Oxypolis rigidior) is a perennial in the — family. Native range includes AR, MO, OK. Hardy in zones 2b–11b. Mature size 2'–5'. Blooms Jul–Sep.

// QUICK FACTS

Family: —
Group: perennial
Native range: Native to 28 U.S. states, including AL, AR, DC, DE, FL, GA…
USDA hardiness: Zones 2b–11b
Mature size: 2'–5'
Sun: Part shade
Water: —
Bloom: Jul–Sep
Wildlife value: Pollinator and wildlife support
Ecological role: native species profile

Stiff cowbane (Oxypolis rigidior) — *Oxypolis rigidior* — Stiff cowbane. Photo by Robert H. Mohlenbrock. USDA SCS. 1989. Midwest wetland flora: Field office illustrated guide to plant species. Midwest National Technical Center, Lincoln. Courtesy of USDA NRCS Wetland Science Institute. via Wikimedia Commons (Public domain).

Field Notes

[ growing · ecology · siting · care ]

Stiff cowbane (Oxypolis rigidior) is a perennial in the — family. Native range includes AR, MO, OK. Hardy in zones 2b–11b. Mature size 2'–5'. Blooms Jul–Sep.

Why it's on this list: native species profile. Native-range data from the Lady Bird Johnson Wildflower Center (NPIN), cross-checked against iNaturalist observations. Part of Rooted Revival's regional native plant catalog — true natives for Oklahoma, Arkansas, Missouri and Kansas.

Companion Planting

[ guild · polyculture · cross-layer pairings ]

In the same native range, stiff cowbane pairs naturally with: Broadleaf Arrowhead (Sagittaria latifolia), Blue-Eyed Grass (Sisyrinchium angustifolium), Butterfly Milkweed (Asclepias tuberosa), Cardinal Flower (Lobelia cardinalis).