Perennial herbs. Root thin, fibrous, or thick taproot. Radical leaves forming basal rosettes. Rosulate leaves sessile, fleshy, oblong, spathulate, obovate, elliptic, linear, attenuate at the base, entire. Flowering stems arising from the axils of the rosulate leaf, unbranched, erect, glandular hairy or glabrous, deciduous. Cauline leaves fleshy, simple, alternate, sessile, oblong to spathulate, entire, glandular hairy or glabrous. Inflorescence terminal or lateral, corymbose, paniculate, lax thyrse, sometimes solitary. Flowers 5-9 merous, bisexual, glandular hairy or glabrous, campanulate-infundibular, sessile or pedicellate. Calyx gamosepalous, lobes green, fleshy, connate at the base, campanulate. Corolla gamopetalous, lobes membranous, united 1/10-3/4 of their length, white, pink or red, glabrous or glandular hairy. Stamens 10-18, epipetalous, in two whorls, basifixed. Nectar scales oblong or square, apex rounded or truncate. Carpels superior, apocarpic but basally syncarpic, ovaries sessile, straight. Follicles erect, free, several to many-seeded. Seeds oblong-ellipsoidal, brown with longitudinal striae.