The growth habits of cacti vary greatly from low growing pin-cushion types to some columnar ones that are almost shrubby or tree-like. Here are some of the latter.
Native to Mexico, this columnar cactus grows to about 13 feet or so in height. This branching plant has six ribs along the blue-green columns. It has very few spines. The whitish-green blossoms open during the day. This plant produces edible fruits.
This species is native to Peru. It has a number of columns that form a rounded clump. Nearly 4½ feet in height, the many-ribbed columns are completely covered with yellowish-gold spines. Opening during the night, the lovely flowers are red.
Little star big-spine
Native to Mexico, this cactus has slender branching columns that over time become tree-like. This can grow to be around 20 feet in height.
The bright green columns can have as many as eight ribs. This plant is covered with pale spines. It produces lovely yellow blossoms, which eventually can bring a crop of purple fruits. These edible fruits are delicious.
Organ pipe cactus
These cacti are particularly well known. Native to Mexico and parts of the American Southwest, there are several species of these plants. These have branching, tree-like columns. Along the stems are sharp ribs, which usually have spines. When small, this plant makes an excellent houseplant.
The attractive blossoms are very beautiful. Typically, these will be either pink or white. Mostly tubular to funnel-shaped, these emerge during the daylight hours.
The fruits of some organ pipe cactus are edible. There are several species, including the Arizona organ-pipe, which can reach about 20 feet in height. Several other species are found in Mexico.
Peruvian column cactus
This is a commonly grown kind of cactus. The parentage of this plant is unknown. But, some believe it is a hybrid. With numerous branches, the blue-green columns have about ten ribs. These are dotted with a few brown spines. This plant has lovely white flowers.
South American blue column
Native to Colombia, this has a tree-like appearance with columns that reach nearly 50 feet in height. The blue-green columns have six or so ribs with a limited number of spines. This produces white blossoms.
Totem pole cactus
Native to parts of the Southwestern U.S. and Mexico, this has delicate, slender green columns. These are sharply angled with nine ribs or so. This plant has dark green spines. From the areoles arise white woolly threads that appear in clusters. The scarlet-red flowers open during the night.