Cereus are shrubby or treelike, often attaining great heights (C. hexagonus, C. lamprospermus, C. trigonodendron up to 15 m). Most stems are angled or distinctly ribbed, ribs 3–14 cm long, usually well developed and have large areoles, usually bearing spines. Cephalium is not present, Cereus mortensenii develops pseudocephalium. Flowers are large, funnelform, 9–30 cm long, usually white, sometimes pink, purple, rarely cream, yellow, greenish, and open at night. Fruits are globose to ovoid to oblong, 3–13 cm long, fleshy, naked, usually red but sometimes yellow, pulp white, pink or red. Seeds large, curved ovoid, glossy black.