The rainbow cactus is a small, columnar cactus wrapped in dense bands of pink, white, and rose-colored spines that circle the stem like stripes on a stick of candy. In spring, mature plants crown themselves with large magenta-pink blooms nearly as wide as the plant itself.

It wants strong sun, a fast-draining cactus mix, and water only when the soil has dried completely; ease off almost entirely in winter. Protect it from frost and from soggy soil. It is a slow, tidy grower that stays windowsill-sized for years.