Herbs, 15–80 cm. Flowers: petals usually blue, (8–)12–23 mm; styles 6–12 mm.

Flowering Apr–Aug. Semideserts, mesas, prairies, dry calcareous glades, barrens, alpine meadows, arctic tundra; 0–3600 m; Alta., B.C., Man., N.W.T., Nunavut, Ont., Que., Sask., Yukon; Alaska, Ariz., Ark., Calif., Colo., Idaho, Kans., La., Minn., Mo., Mont., Nebr., Nev., N.Mex., N.Dak., Okla., Oreg., S.Dak., Tex., Utah, Wash., W.Va., Wyo.; Mexico (Baja California, Chihuahua, Coahuila, Durango, Mexico, Nuevo León, Sonora).

T. Mosquin (1971) found that within populations of var. lewisii variation in height, branching, flower and fruit size, and the relative lengths of styles and stamens was low, whereas these characters differed considerably among populations. Populations of var. lewisii in the central and eastern United States (Louisiana, Missouri, West Virginia) are most likely recent introductions (C. M. Rogers 1984), as are populations in Ontario and Quebec (J. D. T. Becker 2010). Some populations in Minnesota appear to be hybrids between var. lewisii and Linum perenne.