What Is Meant by Fast-Growing Cactus?

Growth Rate

• Plants labeled as fast growers gain 25 inches or more in height per year, according to the Arbor Day Foundation. Such plants are often cultivated outdoors due to their sheer size, but this isn't always the case. Some large cactuses make excellent floor plants, according to Aggie Horticulture. Just make sure any container housing a cactus plant has drainage holes in its base.

Correct Climate

• Climate is an important consideration when it comes to cactus care. Although many cactus species grow best in hot, dry conditions, some can tolerate very cold conditions. Depending on the species, cactus grows in U.S. Department of Agriculture plant hardiness zone from 3 to 11, -- the cold-hardiest being the prickly pear cactus (Opuntia spp.) which has edible paddles and fruits and grows in USDA zones 3B to 11. The saguaro cactus, symbol of the American West and known as the "king of cactus" grows only in the Sonoran Desert in USDA zones 9A to 10B.

Correct Culture

• Culture is equally important if your cactus is going to grow as quickly as possible. Although the family is large and diverse, all cactuses share the same basic care requirements, according to the Texas A&M Aggie Horticulture website. They don't like to be overwatered, so if you live in a wet climate, take care not to plant your fast-growing cactus in a depression where water will collect. When watering a potted cactus, wait until the top inch or so of the planting medium is dry to the touch, and ensure the pot has drainage holes. And although cactus is a desert icon, some species actually prefer shade, so make sure you know the preferences of your particular species. In general, most of the spiny or fuzzy types thrive in full sun, while many of the smooth-skinned types like the shade.

Fast-Growing Cacti

• The Mexican fencepost (Pachycereus marginatus) is a fast-growing columnar cactus recommended as a low-water use plant by the Arizona Municipal Water Users Association. Hardy in USDA zones 9B through 11B, it can grow up to 3 feet per year and will quickly reach a maximum average height of between 12 and 15 feet. The cactus branches out with 6-inch-wide columns and can be used for privacy fencing. Hildmann's Cereus (Cereus hildmannianus), also known as hedge cactus, queen of the night and Andes organ pipe, is another recommended fast-growing cactus. Resembling the saguaro cactus, also known as the organ pipe cactus, the Andes organ pipe quickly reaches heights of 15 feet and is hardy in USDA zones 9 through 11.