Cereus peruvianus (torch cactus, hedge cactus, torch thistle) is a columnar cactus that can grow very large. Despite its name, it did not come from Peru; it probably originated someplace in central Brazil.
Torch Cactus. See more pictures of cacti.
When mature, it develops heavy branches. Indoors, it can grow quite large; there is sometimes a problem keeping it upright when it gets top-heavy. The stems have five to eight flat ribs that often have clusters of brown spines along the outside edge. It makes an excellent hedge that is better at containing cattle than barbed wire. The mature plants have large, white flowers and bloom quite profusely.
Give it bright light, heavy soil with good drainage and house temperatures. Drench and let dry, but be careful not to overwater in the winter time or it will rot. Give it a bath every so often to free it of dust and grime.
It grows very easily from seed and will produce a great variety of forms-lumpy, bumpy and monstrous-from a single fruit. You can tell if a plant has been grown from a seedling or a cutting-the cuttings are fat at the bottom and the seedlings are thin at the base. Strong growers, torch cactus plants are often used as root stocks for grafting.
Caring for your cactus: