Perennials; glabrous or sparsely hirsute. Rhizomes cylindrical, slender, to 2 mm diam. Stems erect, unbranched, 1.5-5 dm, glabrous or sparsely hirsute basally. Rhizomal leaves absent. Cauline leaves 4-7, simple, (crowded distally), petiolate; petiole (0.5-)1-4(-5) cm, base not auriculate; blade usually broadly ovate or ovate-lanceolate to ovate-elliptic, rarely obovate, 5-13 cm × 20-65 mm, base cuneate, margins coarsely serrate (with apiculae), or repand to undulate (margins minutely pubescent, apex acute). Racemes ebracteate. Fruiting pedicels divaricate-ascending to suberect, 10-22 mm. Flowers: sepals oblong, 6-8 × 2-2.5 mm, lateral pair slightly saccate basally; petals pink, oblanceolate, 15-28 × 5-8 mm, (claw to 10 mm, apex rounded); filaments: median pairs 8-10 mm, lateral pair 4-6 mm; anthers linear, 2-3 mm. Fruits linear, 2.5-3.5(-5) cm × 1.9-2.1 mm; ovules 12-16 per ovary; style 2-3.5 mm. Seeds brown, oblong, 2-2.5 × 1.2-1.5 mm.

Flowering May-Jun. Moist cliffs, wooded creek bottoms, shaded draws, hillsides, moist woods, mixed coniferous forests, granitic soils; 400-600 m; Idaho.

Cardamine constancei is known from Clearwater, Idaho, Kootenai, Nez Perce, and Shoshone counties.