The shrubby Cylindropuntia leptocaulis plants reach 5 to 1.8 m (1.6 to 5.9 ft) tall, reaching the extreme height when supported within desert trees. Branches are narrow, 3–5 mm across. Spines 0-1 (occasionally as many as 3) at each areole. Flowers open in the late afternoon and are pale yellow or greenish yellow, with occasional red tips.