Common camas is a stout, robust, 12-28 inches (30-70 cm) tall plant with a dense inflorescence. Camases are liliaceous, perennial herbs that grow from an edible bulb. The leaves are long and narrow, grass-like, and emerge from the base. The flowers are light to deep blue; more than 3 flowers in an inflorescence may be open at one time. Flowers have 6 tepals, 6 stamens, and 3 stigmas. The inflorescence is a spike-like cluster borne on a leafless stem that is held above the leaves. Common camas is distinguished from great camas (Camassia quamash ssp.quamash) by the following: the flowers are slightly irregular, with the lowest tepal curving outward away from the stem; the anthers are bright yellow; the plant is relatively short and stout, with shorter flower stalks and smaller bulbs; and there is no waxy powder on the leaves. Common camas blooms from April through June. The fruits are barrel-shaped to three-angled capsules,splitting into three parts to release many black, angled seeds.

The bulbs were highly prized by Coast Salish peoples for their creamy potato or baked pear taste.