The organ pipe cactus (Stenocereus thurberi) is so named because of its multi-limbed grow habit which does resemble the pipes of the grand organs found in churches. You can only grow organ pipe cactus in warm to hot climates where there is room for a 26-foot (7.8 m.) tall plant. However, the cactus is slow growing, so planting organ pipe cactus in a container for a few years is a fun way to grow this interesting plant.
Planting Organ Pipe Cactus
Organ pipe cactus grows well in well-drained, gritty soils. Planting the cactus in an unglazed clay pot will allow excess moisture to evaporate. Use either a cactus mix or make your own with one part potting soil, one part sand and one part perlite. Immerse the cactus in the soil up to the bottom of the stems and press the soil around it to firm. Put a mulch of tiny rocks on top of the soil to conserve moisture and prevent weeds. Place the cactus indoors where temperatures are 70 -80 degrees F. (21-27 C.) in full sun.
Grow Organ Pipe Cactus
Organ pipe cactus is a wild growing plant found in hot, sunny southern Arizona. The cactus’ habitat is rocky, sandy and generally inhospitable and unfertile. Organ pipe cactus stems are generally about 16 feet (4.8 m.) long, and the entire plant can attain 12 feet (3.6 m.) in width. The stems are ribbed with 12 to 19 inch (30 to 47.5 cm.) thick ridges. The entire plant is covered in black spines that become lighter as they get older. The organ pipe cactus lives a long time and doesn’t reach maturity until it is 150 years old.
Organ pipe cactus care is highlighted by watering. The most common cause of potted cactus failure is over irrigating the plant. The cactus is used to low fertility, but as a potted plant has limited access to resources. Give it a good cactus food in the irrigation water in early spring. Do not water in the winter from November to February.
Watch for pests, such as scale sucking insects, and use an insecticidal soap to combat them. You can put your potted cactus outdoors year round in USDA zones 9 to 11.
Organ Pipe Cactus Flowers
As they mature and grow, organ pipe cactus produce large flowers. The blooms are pure, snowy white with pink or purple edging and 3 inches (7.5 cm.) across. The flowers are held well out from the cactus to help bats and insect pollinators access the bloom. The flower is primarily pollinated at night by bats or perhaps moths. The flower opens at night and closes in the day. April, May and June are the best times to see organ pipe cactus flowers.
The flowers yield to large juicy fruits with bright red flesh. Homegrown organ pipe cactus are unlikely to produce flowers unless they have been in the landscape for over a century, but you can travel to the Organ Pipe National Monument in Arizona to view the spectacular flowers.