// SPECIES PROFILE · ANNUAL · NATIVE

Large st. john's-wort

Hypericum majus

Large st. john's-wort (Hypericum majus) is a annual in the — family. Native range includes KS, MO, OK. Hardy in zones 2a–9b. Mature size 1"–28". Blooms Jul–Sep.

// QUICK FACTS

Family: —
Group: annual
Native range: Native to 28 U.S. states, including CO, CT, DE, IA, ID, IL…
USDA hardiness: Zones 2a–9b
Mature size: 1"–28"
Sun: —
Water: —
Bloom: Jul–Sep
Wildlife value: Pollinator and wildlife support
Ecological role: native species profile

Large st. john's-wort (Hypericum majus) — *Hypericum majus* — Large st. john's-wort. Photo by aarongunnar https://www.inaturalist.org/people/aarongunnar via Wikimedia Commons (CC BY 4.0).

Field Notes

[ growing · ecology · siting · care ]

Large st. john's-wort (Hypericum majus) is a annual in the — family. Native range includes KS, MO, OK. Hardy in zones 2a–9b. Mature size 1"–28". 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, large st. john's-wort pairs naturally with: Common Sunflower (Helianthus annuus), Swamp verbena (Verbena hastata), Slim amaranth (Amaranthus hybridus), Annual ragweed (Ambrosia artemisiifolia var. artemisiifolia).