Large Ornamental Cactus Plants

Saguaro

• This towering cactus consists of one tall column with several branches curving upward like arms. A Saguaro (Carnegiea gigantea) only grows about 1 inch per year but can reach 15 to 50 feet when mature. In May and June, a white flower blooms at the end of each tube. The flower opens on cooler nights and closes in the midday heat. For its size and weight, the saguaro has a shallow root system. This cactus needs support in windy areas.

Senita

• Groups of 5 to 20 tall columns branch out near the base and curve upward, resembling organ pipes. This succulent reaches about 12 feet in height and spreads about 8 feet. When the senita (Pachycereus schotti) stems reach flowering stage, a tuft of twisted, bristle-like spines appear. Small, pink, nocturnal flowers bloom on the stems' tips from April through September. This cactus is sensitive to temperatures of 25 degrees or colder.

Barrel

• The unusual cylindrical shape and thick, fishhook spines make the barrel cactus (Ferocactus) special. Prominent ribs allow it to swell during a rain and shrink during droughts. It grows from 4 to 11 feet tall and 2 feet in diameter. From April through June, a crown of yellow, orange or red flowers bloom on the plant's top. As it ages, it leans south toward the sun. This cactus is frost tolerant.

Prickly Pear

• Large, fleshy, flat pads resembling leaves distinguish the fast-growing prickly pear cactus (Opuntia). It reaches a height of 3 to 4 feet, but placing it in a raised bed makes it appear taller. If a spreading cactus is desired, the prickly pear may extend as far as 20 feet. This genus has a variety of pad shapes and colors. Depending on the species, from early spring through summer it has yellow, orange or red blooms. The prickly pear adapts to different soils and climates and is both heat and cold hardy.

Chain-Fruit Cholla

• Tree-like in appearance, the chain-fruit cholla cactus (O. fulgida) has a central trunk with spiny, jointed branches. A heavy layer of spines covers the branches. As the cactus ages, the spines fall off the trunk, leaving a rough, gray bark. This species grows up to 15 feet high and 6 feet across. From June to August, white and pink flowers streaked with lavender bloom on the ends of the stems. This cactus withstands very cold temperatures.