From our perspective as Echeveria plants, we are resilient succulents, but our succulent leaves and tight rosettes can unfortunately become a home and food source for several pests. These infestations are a significant stressor, hindering our ability to photosynthesize and grow properly. Here is a detailed account of the common adversaries we face and the treatments that can help us recover.
We find mealybugs to be one of the most common and frustrating pests. They appear as small, cotton-like masses nestled in the most protected parts of our being—the crevices between our leaves, at the base of our stem, and even on our roots. They pierce our tissue with their needle-like mouthparts and suck out our vital sap, which weakens us and can cause our leaves to yellow and wilt. The honeydew they excrete also encourages the growth of sooty mold, which further blocks sunlight from our surfaces.
To treat them, we greatly benefit from a physical intervention. A cotton swab dipped in isopropyl alcohol (70%) and dabbed directly onto the pests dissolves their waxy coating, effectively eliminating them on contact. For larger infestations, a gentle spray of a soapy water solution or a horticultural oil can suffocate the bugs without harming our farina, our precious powdery protective coating, if applied carefully and out of direct sunlight.
Aphids typically attack our tender new growth, such as emerging flower stalks and the center of our rosettes. These small, soft-bodied insects (green, black, or brown) cluster together and drain our energy, causing new leaves to become distorted and stunted. Like mealybugs, they produce honeydew.
A strong jet of water can often dislodge a small aphid colony. For persistent problems, insecticidal soap sprays are very effective. As a preventative measure, we appreciate the introduction of natural predators like ladybugs to our environment, who see these aphids as a tasty meal.
Spider mites are tiny arachnids that are difficult to see until their damage is advanced. They create fine, silky webbing, usually on the undersides of our leaves. They feed by piercing our cells, which leads to a characteristic stippling pattern—tiny yellow or white spots—across our foliage. A severe infestation can leave us looking bronzed, drained, and desiccated.
Since they thrive in hot, dry conditions, increasing humidity around us can deter them. Regularly spraying our foliage with water can help dislodge them and their webs. Miticides or neem oil applications are often necessary to control a significant population, ensuring thorough coverage, especially under the leaves.
The adult fungus gnats are mostly a nuisance, but their larvae in the soil are the real problem for us. These tiny white worms feed on organic matter and, more distressingly, chew on our delicate root systems. This root damage hinders our ability to uptake water and nutrients, leading to stunted growth and a general decline in our health.
The key to control is managing soil moisture. Allowing the soil to dry thoroughly between waterings is the most effective method, as the larvae cannot survive in dry conditions. Using yellow sticky traps can catch the adult gnats and help monitor the population. In severe cases, a soil drench with a biological control like Bacillus thuringiensis israelensis (Bti) can target the larvae without harming us.
Scale insects appear as small, brown, bump-like growths attached to our stems and the undersides of our leaves. They are protected by a hard, armored shell and, like mealybugs, feed on our sap. A heavy infestation can cause leaf yellowing, drop, and a general lack of vigor.
Individual scales can be carefully scraped off with a fingernail or a soft brush. For larger problems, horticultural oil sprays are effective as they can seep under the scale's armor and suffocate the insect beneath. As with all sprays, application should be done during cooler parts of the day to prevent leaf burn.
