// SPECIES PROFILE · PERENNIAL · NATIVE

Illinois horse-gentian

Triosteum aurantiacum var. illinoense

Illinois horse-gentian (Triosteum aurantiacum var. illinoense) is a perennial in the — family. Native range includes AR, KS, MO, OK. Hardy in zones 3a–8a. Mature size 6"–4'. Blooms Apr–Jul.

// QUICK FACTS

Family: —
Group: perennial
Native range: Native to 30 U.S. states, including AR, CT, DC, DE, GA, IA…
USDA hardiness: Zones 3a–8a
Mature size: 6"–4'
Sun: —
Water: —
Bloom: Apr–Jul
Wildlife value: Pollinator and wildlife support
Ecological role: native species profile

Illinois horse-gentian (Triosteum aurantiacum var. illinoense) — *Triosteum aurantiacum var. illinoense* — Illinois horse-gentian. Photo via iNaturalist — (c) bobkennedy, some rights reserved (CC BY-SA), uploaded by bobkennedy.

Field Notes

[ growing · ecology · siting · care ]

Illinois horse-gentian (Triosteum aurantiacum var. illinoense) is a perennial in the — family. Native range includes AR, KS, MO, OK. Hardy in zones 3a–8a. Mature size 6"–4'. Blooms Apr–Jul.

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, illinois horse-gentian pairs naturally with: Broadleaf Arrowhead (Sagittaria latifolia), Butterfly Milkweed (Asclepias tuberosa), Cardinal Flower (Lobelia cardinalis), Common Blue Violet (Viola sororia).