Ultimate Guide: Identifying and Controlling Cactus Pests

When you think of a cactus, the first thing that comes to mind is probably not pests. But you’d be surprised to find out that these prickly survivors are not immune to pesky critters looking for food and shelter. Cacti have evolved numerous defense mechanisms to thrive in harsh desert environments, but pests can still pose a threat.

In this in-depth guide, we will walk you through everything you need to know about identifying and controlling 11 common cactus pests. From aphids to vertebrates, we’ve got you covered. So, let’s dive in and boogie our way through pest management!

The 11 Types of Cactus Pests

1. Aphids
2. Coreids
3. Fungus Gnats
4. Longhorn Beetles
5. Mealybugs
6. Moths
7. Root-Knot Nematodes
8. Scale
9. Slugs and Snails
10. Spider Mites
11. Vertebrates

But before we delve into the specifics of each pest, here are some important things to keep in mind when dealing with cactus pests:

• Compatibility of Chemical Controls: Cacti have protective coatings that can be sensitive to certain insecticidal soaps and oils. Always check the compatibility of your chosen chemical controls before application.
• Test on a Small Portion: When in doubt, test your chemical controls on a small part of your plant before widespread application.
• Evening Application: If using harsh chemicals, apply them in the evening to minimize sun damage.
• Healthy Plants = Pest Prevention: Healthy plants are less susceptible to pest infestations. Proper cultivation practices are crucial for preventing pest problems.

How to Control Specific Cactus Pests

1. Aphids

Aphids are tiny, soft-bodied insects that can wreak havoc on cacti by extracting vital fluids and leaving behind honeydew that promotes the growth of black sooty mold. To control aphids:

• Use strong sprays of water to blast aphids off infested surfaces.
• For indoor plants, use gentle sprays of horticultural oil or diluted isopropyl alcohol.
• Soil drenches of imidacloprid or dinotefuran can be used for root-infesting aphids.

2. Coreids

Also known as cactus bugs, coreids are true bugs that feed on cacti flowers, fruits, and pads, leaving behind light-colored blemishes. To control coreids:

• Use appropriate insecticidal soaps and horticultural oils for nymphs.
• Adults can be managed with foliar sprays or soil drenches containing imidacloprid.
• Acetamiprid can be used as an environmentally benign neonicotinoid option.

3. Fungus Gnats

Fungus gnats are soilborne pests that feed on cacti roots. To control fungus gnats:

• Avoid overwatering to prevent egg laying.
• Allow soil to dry out in full sun.
• Read more about protecting plants from fungus gnats.

4. Longhorn Beetles

Longhorn beetles feed on tender cacti growth and can cause significant damage. To control longhorn beetles:

• Remove beetles manually using tweezers in the evenings.
• Kill beetles before egg laying to prevent larval damage.
• Learn more about longhorn beetles in our guide.

5. Mealybugs

Mealybugs are oval-shaped pests that extract plant juices and excrete honeydew. To control mealybugs:

• Knock mealybugs off with strong sprays of water.
• Use 70 percent isopropyl rubbing alcohol on mealybugs.
• Direct applications of permethrin and neem oil can also be effective.

6. Moths

Cactus moths can hollow out cactus pads by consuming them from the inside out. To control cactus moths:

• Remove egg sticks promptly.
• Consult local extension agents for additional recommendations.
• Learn more about cactus moths in our guide.

7. Root-Knot Nematodes

Root-knot nematodes puncture cactus roots, causing knots that limit water and nutrient uptake. Prevention is key to managing nematodes:

• Use sterile soils and soilless media to prevent nematodes.
• Additional tips can be found in our nematode control guide.

8. Scale

Multiple types of scale can infest cacti, causing weakened vigor. To control scale:

• Quarantine infested plants to prevent spread.
• Use strong bursts of water, hand removal, or sprays of isopropyl alcohol and insecticidal soap.
• Learn more about scale management in our guide.

9. Slugs and Snails

Slugs and snails can feed on cactus spines, leaving irregular holes. To control slugs and snails:

• Modify the environment to remove shelters for pests.
• Use traps or hand removal methods.
• Visit Gardener’s Supply Company for effective traps.

10. Spider Mites

Spider mites can cause chlorosis and deterioration in cacti by sucking out plant juices. To control spider mites:

• Use insecticidal soap, neem oil, or strong sprays of water.
• Learn more about managing spider mites in our guide.

11. Vertebrates

Birds and mammals can also feed on cacti, causing unsightly damage. To deter vertebrates:

• Use visual and auditory deterrents for birds.
• Surround specimens with wire fencing to keep out rabbits and gophers.
• Place mint plants as a natural deterrent.
• Learn more about vertebrate control in our guide.

Final Thoughts

Managing cactus pests takes practice, but with the right knowledge and tools, you can keep your plants healthy and thriving. Remember, prevention is key, and healthy plants are less susceptible to infestations. If you have any questions or pest problems of your own to share, feel free to leave a comment below.

Now that you’re armed with the know-how to tackle cactus pests, put your knowledge into action and watch your cacti flourish. Happy gardening!