// SPECIES PROFILE · ANNUAL · NATIVE

Grand redstem

Ammannia robusta

Grand redstem (Ammannia robusta) is a annual in the — family. Native range includes AR, KS, MO, OK. Hardy in zones 2a–11a. Mature size 1"–40". Blooms May–Nov.

// QUICK FACTS

Family: —
Group: annual
Native range: Native to 29 U.S. states, including AR, AZ, CA, CO, IA, ID…
USDA hardiness: Zones 2a–11a
Mature size: 1"–40"
Sun: —
Water: —
Bloom: May–Nov
Wildlife value: Pollinator and wildlife support
Ecological role: native species profile

Grand redstem (Ammannia robusta) — *Ammannia robusta* — Grand redstem. Photo by John Scholze via Wikimedia Commons (CC BY 2.0).

Field Notes

[ growing · ecology · siting · care ]

Grand redstem (Ammannia robusta) is a annual in the — family. Native range includes AR, KS, MO, OK. Hardy in zones 2a–11a. Mature size 1"–40". Blooms May–Nov.

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, grand redstem pairs naturally with: Common Sunflower (Helianthus annuus), Swamp verbena (Verbena hastata), Annual ragweed (Ambrosia artemisiifolia var. artemisiifolia), Nodding beggartick (Bidens cernua).