Plants perennial; taproot thick, fleshy; caudex branched. Stems 1-several, straggling to erect, sometimes decumbent at base, simple or much-branched distally, 20-120 cm, puberulent or scabrous-pubescent, sometimes retrorse, often glandular distally, becoming glabrate proximally. Leaves sessile or narrowed at base into pseudopetiole, blade pubescent on both surfaces; proximal with blade lanceolate and oblanceolate, broadest distally or distal often reduced, cauline longest near mid stem, blade linear to lanceolate or elliptic, 1.5-10 cm × 2-30 mm. Inflorescences from 1-flowered to simple dichotomy to compound and 3-5-many-flowered with elongate branches; bracts small, linear-lanceolate, or resembling leaves. Pedicels elongate, much exceeding calyx. Flowers: calyx green, 10-veined, broadly tubular, 12-25 × 4-8 mm in flower, narrower towards base, middle broadening to 6-13 mm in fruit, narrower at both ends, pubescent, glandular, lobes lanceolate, 2.5-5 mm, margins membranous or not, apex ± obtuse; corolla scarlet, clawed, claw equaling or longer than calyx, limb lobed, often deeply so, lobes 4-6, linear, lanceolate, or oblong, small lateral teeth may be present, 6-15 mm, appendages inconspicuous, 1-2 mm, dentate; stamens longer than corolla claw but shorter than lobes; stigmas 3, equaling corolla. Capsules oblong to ovoid or broadly tubular, equaling calyx, opening by 6 ascending teeth; carpophore 2-4 mm. Seeds reddish brown, broadly reniform, 1.7-2.3 mm, sides tuberculate, margins papillate. The large, beautiful scarlet flowers of Silene laciniata are bird- and butterfly-pollinated. The species occurs in three forms. Subspecies laciniata has narrow leaves, much-branched and many-flowered, open inflorescences, and oblong capsules. Subspecies californica has ovate to lanceolate leaves, few-flowered inflorescences, and ovoid capsules. These two entities both occur in California and Mexico. Although they are usually distinguishable, apparent intermediates occur. The third entity is subsp. greggii, which occurs in Arizona, southwestern Texas, and Mexico. It combines characters of the other two subspecies, having broader leaves, a branched and many-flowered open inflorescence, and a capsule of intermediate shape.

Plant: Perennial forb 20-50 cm; herbage glandular Leaves: leaves opposite, lance-ovate 2-6 cm long, sessile Flowers: flowers reddish-orange, showy, ~4 cm long, deeply notched Fruit: a many seeded capsule.