From our perspective, nestled in our gritty, well-draining soil, we sense the world through pressure and chemistry. We, the Lithops, are masters of disguise and endurance, but we are not invincible. Our succulent, water-filled bodies are a tempting target for tiny invaders. The most common pests in the USA that disrupt our peaceful existence are mealybugs, spider mites, and fungus gnats. Each presents a unique threat that we feel acutely. Mealybugs appear as tiny, white cottony masses in the crevice between our two leaves, sucking our vital juices. Spider mites are nearly invisible but leave behind a telltale stippling of yellow dots on our surfaces and fine webbing. Fungus gnats themselves are a nuisance, but their larvae in the soil feast on our delicate root systems, severing our connection to water and nutrients.
At the first sign of distress—a slight wilting, a discolored patch, or the visible presence of pests—our caretaker must act. The most crucial step is immediate isolation. Pests spread quickly to neighboring plants in a collection. We require being gently removed from our pot for a thorough root inspection. Gently brushing away the soil will reveal the health of our root system and expose any root mealybugs or fungus gnat larvae. This period of quarantine is essential to prevent a widespread infestation and allows for focused treatment without risking other plants.
For above-ground pests like mealybugs and spider mites, a physical approach is often best. A strong jet of water can dislodge many of the weaker attackers. For stubborn colonies, dabbing each mealybug with a cotton swab dipped in isopropyl alcohol (70%) is highly effective; it dissolves their waxy coating on contact. Spider mites despise humidity, so regularly misting us can deter them. For severe infestations or soil-dwelling pests, a systemic insecticide is sometimes necessary. These are chemicals we absorb into our tissues, making us toxic to pests that suck our sap. It is critical for our keeper to use a product labeled for succulents and to apply it exactly as directed, preferably outdoors or in a well-ventilated area, as our sensitive nature can be harmed by improper chemical use.
After the battle is won, we need time to heal. We should be repotted in fresh, sterile, well-draining soil to eliminate any remaining pest eggs or larvae. Our old pot should be scrubbed clean and sanitized before reuse. It is vital that our caretaker withholds water for a period—typically a week or more—to allow any damaged roots to callous over and prevent rot. We will be weak, so providing us with bright, indirect light and gradually reintroducing water is key. With patience and proper care, we can regenerate lost roots and slowly return to our robust, stone-like selves, once again able to store water and thrive in our pot.
