Aloe vera is a popular succulent prized for its soothing gel and is often considered a resilient, low-maintenance houseplant. Despite its hardy nature, the plant is not immune to organisms that view its thick, water-rich leaves as sustenance. From microscopic insects to larger garden animals, several species can cause significant damage to the plant’s health and appearance. Identifying these threats is the first step in protecting your plant collection.
Common Pests That Feed on Aloe Vera
The most frequent culprits are small, sap-sucking insects often introduced in potted or indoor environments. Mealybugs appear as soft-bodied, cottony masses and cluster in protected crevices where the leaves meet the stem. They pierce the plant tissue and extract sap, which weakens the plant.
Scale insects are another common pest, presenting as small, hardened brown or gray bumps. These stationary pests feed on sap and are difficult to remove due to their protective, waxy shell.
A destructive threat is the microscopic aloe mite, which is not visible but injects a chemical causing cancerous-like growth. These mites target the plant’s growth points, leading to permanent deformation of the leaves and flower stalks. Other pests include spider mites, which thrive in dry conditions and cause fine webbing, and aphids, which congregate on new, tender growth. Sap-suckers can also lead to sooty mold, which grows on the sticky “honeydew” residue they excrete.
Diagnosing Damage Based on Visual Symptoms
Determining the cause of damage relies on observing visual cues left on the leaves. White, fuzzy clumps resembling cotton suggest an infestation of sap-sucking insects seeking sheltered feeding spots. Tiny, shell-like brown or gray bumps fixed to the leaf surface indicate hard-bodied insect pests.
Damage that manifests as distorted, irregular, or tumor-like growths, called galls, points to an attack by microscopic mites. If the leaves exhibit small, pale stippling or mottled yellowing, especially with fine webbing, it suggests the work of minute arachnids. A general loss of turgor, where leaves become limp, or a sudden yellowing of the foliage, signals the plant is being drained of nutrients or struggling with root issues.
Larger Animals and Outdoor Consumption
When cultivated outdoors, aloe vera is susceptible to consumption by larger animals drawn to its high water content. Rabbits and rodents, such as rats or gophers, may chew on the plant. Rabbits leave clean-cut edges on the leaves.
Rodents, particularly gophers and voles, often cause damage below the soil line by feeding on the roots and underground stem, which can lead to the plant collapsing. Slugs and snails also feed on the tender leaves, creating large, irregular holes. A silvery, slimy trail across the leaves indicates a mollusk is the culprit. This damage is most common during high humidity or after rainfall, as these animals prefer moist conditions.
Effective Treatment and Prevention Strategies
Addressing a pest infestation often begins with non-chemical methods for minor outbreaks. For soft-bodied pests like mealybugs and aphids, a cotton swab dipped in 70% isopropyl rubbing alcohol can be pressed onto the insects to destroy their waxy coating. For larger infestations, a strong spray of water can physically dislodge pests like aphids and scale.
Horticultural oils, such as neem oil, offer an organic solution that can be sprayed over the entire plant to suffocate many insect pests, including spider mites and small scale insects. This treatment should be applied thoroughly, coating the undersides of leaves, and re-applied weekly until the pests disappear.
For aloe mites, topical treatments are ineffective because the pests are protected inside the plant tissue. The only recourse is to excise the distorted, gall-like growths with a sterile blade, or in severe cases, discard the entire plant.
Prevention involves adopting cultural practices to make the environment less appealing to pests. New plants should be quarantined for several weeks before being introduced to a collection. Ensure the aloe is potted in a fast-draining substrate and allow the soil to dry completely between waterings to reduce the risk of root rot. For outdoor plants, physical barriers like wire mesh cages can deter rabbits and rodents.