From our perspective, aphids are a significant nuisance. These tiny, soft-bodied insects, often green or black, congregate on our succulent new growth, tender stems, and the undersides of our leaves. Their piercing-sucking mouthparts are inserted into our tissues to drain our vital sap. This direct feeding weakens us, causing our leaves to curl, pucker, and yellow. More alarmingly, aphids excrete a sticky, sugary substance called honeydew, which coats our foliage. This honeydew not only inhibits our ability to photosynthesize effectively but also encourages the growth of sooty mold, further blocking sunlight. To treat us organically, a strong jet of water can dislodge these pests. For persistent problems, insecticidal soaps or neem oil sprays, applied thoroughly to all surfaces, are highly effective and safe options.
Mealybugs are one of the most common pests we face. They appear as small, white, cottony masses nestled in the protected crevices between our leaves and stems, at our base, and even on our roots. Like aphids, they are sap-suckers, and their feeding causes our growth to become stunted and our leaves to yellow and drop prematurely. The honeydew they produce presents the same secondary issues of sooty mold and ant attraction. Their waxy coating makes them resistant to some treatments, so physical removal is a crucial first step. Dabbing each insect with a cotton swab dipped in isopropyl alcohol dissolves their protective layer and kills them on contact. Following this with a thorough application of a neem oil solution helps eliminate any remaining individuals and deters future infestations.
Spider mites are not insects but arachnids, and they are particularly problematic in hot, dry conditions—environments we Crassulas typically enjoy. They are minuscule and often go unnoticed until their damage is severe. From our point of view, the first sign is a subtle stippling or speckling of tiny yellow dots on our leaves where they have been feeding. As the infestation progresses, we may develop a bronze or faded appearance, and fine, silken webbing might become visible, especially between our stems and leaves. Severe infestations can be devastating. Since they thrive in dry air, regularly misting us can help deter them. The most effective organic treatment is a forceful spray of water to break up the webbing and knock the mites off. Insecticidal soaps and neem oil are also very effective against all their life stages when applied consistently.
Scale insects appear as small, brown, bumpy growths attached firmly to our stems and the veins on the undersides of our leaves. They are often mistaken for part of our own structure. These pests are immobile in their adult form, hiding under a protective waxy shell while they insert their mouthparts to feed on our sap. This feeding saps our strength, leading to yellowing leaves, dieback, and a general lack of vigor. Their honeydew excretion is also a problem. Their armor makes them resistant to many sprays. The primary organic method is to physically scrape them off with a fingernail or a soft brush. For larger infestations, horticultural oil can be used to smother them by coating their shells and blocking their spiracles.
