#405 All About Cactus for Southern Nevada
Tough plants for your desert yards
Cacti have interesting shapes and beautiful flowers. They thrive on neglect and come in nearly endless varieties. Ranging in size from a few inches to several feet, cacti can be used as massed plantings, backgrounds or accents. Many species grow well in containers and make attractive, unusual houseplants. Once established, there’s little to do but sit back and enjoy them.
PLANTING: Sandy or rocky soil with good drainage needs very little preparation. Dig the planting hole about 6 inches wider than your container and a couple inches deeper. Fill the hole with water and check the drainage. If the hole doesn’t drain completely within 2-3 hours, dig deeper until it does, or mound the soil so roots won’t be in a soggy spot. Heavy clay soil should be amended. Add washed sand, decomposed granite or a product like Black Gold Cactus Mix to open the soil and improve drainage. Other planting mixes, mulches and starter fertilizers may injure cacti and should be avoided.
Slip the cactus carefully out of its container. Use heavy gloves, an old towel or a piece or of carpet to avoid injuring yourself or your plant. Dust the root ball with soil sulfur or horticultural charcoal to avoid root rot. Ease the cactus into the hole, firm soil lightly around it and water thoroughly. If planting large or top-heavy cacti, seat them a few inches deeper in the hole for extra support. To avoid damaging shallow feeder roots, do not cultivate around the plants.
WATERING AND FERTILIZING: The rule of thumb in watering cacti is “heavily and infrequently” or “less is best.” Once every 2 weeks should be sufficient, except in the hottest exposures where once a week will do just fine. A thorough soaking will simulate our infrequent, heavy summer rains. Do not water from November through February. Withholding water encourages dormancy and will lessen the chances for root rot or excessive freeze damage in bitter cold.
Use Dr. Q’s® Desert Plant & Cactus Food, Fish Emulsion or Blood Meal once or twice from March through May. Fertilization after that time is unnecessary and can be harmful if applied after mid summer. Apply fertilizer over a 2-3 foot area around base of plant and water thoroughly. Once again, do not cultivate fertilizer into the soil.
CACTUS PESTS AND DISEASES: There aren’t many pests that bother cacti but they can be serious. Cactus scale and mealy bugs can cause considerable damage. Pesticides like Malathion, which are normally effective on these insects, can damage some cacti. Test spray a small area and wait 24 hours. If the spot turns brown, or lesions occur, don’t use the product. Water and a stiff-bristle brush or broom are also effective in removing these pests. If you’re not sure of the problem, take samples to a Star Nursery associate for help. Rots comprise the bulk of cacti diseases. They usually occur when the cactus has been injured or over watered. Dust wounds with sulfur and water correctly to prevent these problems.
COMMONLY ENCOUNTERED VARIETIES: The following list is not all-inclusive but shows some of the most popular varieties successfully grown in our area.
Beavertail Cactus (Opuntia species). Smaller, gray-green pads like beaver tails grow in clusters with reddish pink flowers in spring and summer.
Cholla (Opuntia species). Many varieties like Buckhorn, Devil and Teddy Bear may be encountered. Ranging from 4-6 feet or more, they all have vicious spines which means extra care when handled. Flowers range from red to yellow.
Compass Barrel (Echinocactus acanthodes). Round, native cactus with heavy, red spines grows to 5 feet or more with yellow flowers in late spring. Named for its tendency to lean toward the south.
Fishhook Barrel (Ferocactus wislizenii). This native grows slowly to 5 feet or more with yellow to red flowers in summer. Named for red, hook-like spines.
Golden Barrel (Echinocactus grusonii). Round, fat cactus to 2 x 2 feet or more has stiff yellow spines and yellow flowers in spring. Cover with burlap to protect from extreme cold.
Indian Fig (Opuntia species). Tall variety to 8 feet or more with large pads and yellow flowers in late spring. Has edible fruit.
Peruvian Apple Cactus (Cereus peruviana). Treelike growth to 8 feet or more. Large, white flowers produced along the stems open at night during summer. Wrap with burlap to protect from extreme cold. Best when protected from reflected afternoon sun.
Prickly Pear (Opuntia species). Most “paddle cactus” are commonly referred to by this name. Pad size and shape depends on variety. They have red to yellow flowers and edible fruit which makes excellent jelly.
Strawberry Hedgehog (Echinocereus engelmanii). One of our most attractive native cacti. Clusters of small, green globes have straw colored spines and purplish-red flowers followed by strawberry-red fruit.
The Las Vegas Cactus and Succulent Society offers fellowship and detailed help for those who wish to become “experts.” Call the University of Nevada Cooperative Extension, 222-3130, for current phone number of the Society.