Commemorating William Harris, Superintendent of the Public Gardens, Jamaica (Cactaceae). A genus of tall-growing greenhouse succulents, erect when young, becoming sprawling when older. The stems are narrow with few groups of spines. Theare mostly white, nocturnal and fragrant. Some species are used as grafting stock.
H. bonplandii, stem tortuous with few strong spines, flowers large, white, followed by red plum-like fruits, Brazil. H. guelichii, pale green stems young spines, reddish later turning grey, flowers green and white Brazil. H. martinii, stems several feet long, few spines, flower white, Argentina. H. jusbertii, stems mostly erect, branching later, flowers white inside, brownish outside, Paraguay.
A compost consisting of a rich potting compost with a sixth part added of roughage composed of sharp sand, grit and broken brick, is suitable. Repot every two or three years in March. Water March to September as often as thedries out; keep dry from October to March. Grow in a sunny greenhouse and support the growths with a frame or a stick when tall.