From the Greek hyle, wood and Cereus; the plants are found in forests (Cactaceae). A genus of epiphytic cacti, with three-angled or winged stems, often forming aerial roots. Theare large and open at night.
H. antiguensis, stems three-angled, few spines, flowers greenish-white to yellow, Antigua. H. cal-caratus, climbing type with winged joints, flowers cream, Costa Rica. H. lemairei. tall growing, needs support, flowers long, yellowish-green, tipped red, West Indies. H. monacanthus, stems triangular, flowers white with outer petals greenish-yellow, Colombia. H. undatus, thick green stem, useful as a stock for grafting cacti, sometimes found under the name of Cereus triangularis, flowers large, yellow to purple outside, white inside, Central America.
Provide a compost consisting of rich potting compost with added roughage, a sixth part of sand, grit and broken brick. The addition of leafmould is advantageous. Repot every other year in March. Plants must be trained over the roof of the greenhouse or on frames.
Water when dry from March to September, give a little water in winter provided plants are kept warm. Temperatures: 65-75 °F (18-21°C) in the growing period, 55-60 °F (13-16°C) in winter. Provide shade from strong sun.
Propagation is by seed sown as for cacti or by cuttings taken from May to July, dried and rooted in sharp sand and peat, in equal parts.