// SPECIES PROFILE · ANNUAL · NATIVE
Stiff greenthread (Thelesperma filifolium var. filifolium) is a annual in the — family. Native range includes AR, KS, MO, OK. Hardy in zones 5a–10a. Mature size 1"–30". Blooms May–Jul.

[ growing · ecology · siting · care ]
Stiff greenthread (Thelesperma filifolium var. filifolium) is a annual in the — family. Native range includes AR, KS, MO, OK. Hardy in zones 5a–10a. Mature size 1"–30". Blooms May–Jul. Low water use makes it a strong candidate for xeric and drought-conscious plantings.
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.
[ guild · polyculture · cross-layer pairings ]
In the same native range, stiff greenthread pairs naturally with: Black-Eyed Susan (Rudbeckia hirta), Common Sunflower (Helianthus annuus), Plains Coreopsis (Coreopsis tinctoria), Louisiana devil's-claw (Proboscidea louisianica).