How to Identify a Cereus Pest

Learn what the mealybug looks like. These destroy many types of edible cactus and can range in appearance from the alien-looking members of the Cryptolaemus family --- resembling short, fat centipedes in a variety of colors --- to the common ladybug.

Know the difference between beetles that like the taste of your Cereus cactus and those that don't. The cactus longhorn beetle, officially named Moneilema gigas, is about 1 inch long and black with white details at the end of each antenna. Look for them chomping on the edges of your Cereus tubes or at the flower buds.

Inspect your Cereus plants regularly for cochineal scale of the Dactylopius coccus variety. The tiny bugs erect a white shield of cover that resemble tufts of snow, which can be removed with an eraser when found. Look for red splotches under the white when disturbed by the eraser. Application of a hot steam can often remove these insects from the cactus.

Look for other bugs known to snack on your Cereus cacti, like the tiny red spider mite, which will have pale spots on its red back. Other predators include slugs, snails, thrips, ants and aphids. Each requires a different approach for eradication.

Inspect your Cereus cactus regularly for nematode damage. These little worms won't be seen because they infest at the roots and make your cactus look sickly and colorless. A trimming of infected parts and a repotting in worm-free soil will be needed.

Verify the species of any bug you find on your Cereus cactus, and apply the countermeasure recommended by professionals. These range from organic methods like spraying your cactus with a mixture of soap and water to chemical insecticides.