Ocotillo is a spiny shrub to 20 ft. with many long, whip-like, unbranched green stems growing from the base. Stems are leafless most of the year, covering themselves with bright green leaves after a rain. A funnel-shaped plant with several woody, almost unbranched, spiny, commonly straight stems leafless most of the year, and a tight cluster of red flowers at tip of each branch. Scarlet, tubular-shaped flowers are held in terminal clusters. Leaves appear only after rain and wither when the soil dries, a cycle commonly repeated several times during the warm season.