While there are a number of flowering cacti varieties, they can be divided into three basic types. Each shares common characteristics, such as being easy to grow, blooming at night and possessing dense flowers with sweet aromas. Though their natural habitat is the desert, many cacti varieties can be grown as house plants.
All species within the ferocactus genus have long thorns and a cylindrical structure. The flowers measure up to 5 to 6 inches across.
The compass (or California) barrel cactus is tall (4 to 8 feet) with curves and red ribs. It produces bell-shaped yellow and orange flowers.
Wislizenus' (Arizona) barrel cactus is globe-shaped when young and elongated after it reaches 1 foot in diameter. It has numerous white radial spines and grows to a height of from 4 to 11 feet. Flowers are orange, red or yellow and bloom from July to September.
Coville (Sonora) barrel cactus has a purple look and colored spines when it is young. The flowers are yellow, orange or maroon and bloom in July and August. It can grow as tall as 8 feet.
Texas barrel cactus is a small, globe shaped cactus that is green most of the time, but in direct sunlight it may appear purple. The central spine can be as long as 6 inches and the flowers are yellow with reddish bases the bloom from May through July. The Texas barrel cactus is one of the shortest of the barrel cacti, reaching a height of 16 inches.
Strawberry hedgehog cactus has stems that grow from 4 to 12 inches tall and 2 to 4 inches in diameter. The flowers are bright pink, purple or lavender and bloom in the spring, measure up to 3 inches in diameter and 2 to 3 inches long. The flowers close at night and open in the day. The plant usually grows 6 to 8 feet tall, but has been known to reach a height of 20 feet.
The Arizona hedgehog cactus is a mounding cactus that forms from just a few to hundreds of stems. The flowers are funnel-shaped, attract hummingbirds and bloom from April to June. The blooms remain open for 2 or 3 days. It can grow to about 2½ feet tall.
Crimson hedgehog cactus is another small cactus. It grows up to a foot long, grows no leaves and blooms a deep red with petals that form a cup. They bloom from April through June and stay open day and night.
Prickly Pear Cacti
Bunny ears cactus has thorny pears that lie flat on the ground. They can grow to a height of 2 feet, the flowers can be yellow or chartreuse and bloom in mid-spring.
Grizzly bear cactus has stems that are green or reddish purple and spines that are white, yellow to brown, red-brown to gray or black. The spines become gray to dark brown to black as the plant ages. The flowers bloom from late spring to early summer, can be from yellow to magenta and measure 2 inches in diameter. The grizzly bear cactus can grow from 6 to 18 inches in height.