Aloe vera is a popular houseplant, prized for its succulent foliage. Although drought-tolerant and relatively forgiving, the plant suffers when its basic needs are unmet. This guide offers a direct diagnostic approach to identify common problems and determine the cause of distress. Understanding symptoms related to moisture, environment, and pests can help restore your aloe to health.
The Primary Culprit: Issues Related to Watering
The majority of problems encountered with Aloe vera plants stem from improper moisture management, either due to over- or underwatering. As a succulent, the plant stores water within its thick, fleshy leaves, making it highly susceptible to damage if the soil stays saturated for too long. Saturated soil leads directly to the breakdown of root tissue, known as root rot.
Root rot symptoms include leaves that become soft, mushy, and translucent, often turning a pale yellow or brown color starting from the plant’s base. Inspect the roots if you suspect this issue. Healthy roots are firm and white or light brown, while rotting roots appear black, slimy, and emit a foul odor.
To correct severe overwatering, immediately prune away all affected, slimy root tissue using clean, sharp tools. Allow the remaining healthy root system and the base of the plant to dry out, or “callus over,” for several days. Repot into fresh, well-draining succulent soil. Withhold water for at least a week after repotting to allow the plant to stabilize and begin forming new roots.
Conversely, an underwatered aloe will display completely different symptoms, indicating that the plant is consuming its own stored moisture for survival. The leaves appear thin, shriveled, and wrinkled, losing their plump, firm texture. The tips of the leaves may also turn brown or yellow as the plant dehydrates.
To remedy severe dehydration, water the plant thoroughly until moisture drains fully from the pot’s drainage holes. Allowing the plant to sit in a saucer of water for up to 15 minutes can ensure the dry soil fully rehydrates, a method known as bottom-watering. Adjust the watering schedule to apply water only when the top two inches of soil are completely dry to the touch. This approach ensures the plant receives sufficient moisture without creating an environment conducive to root rot.
Environmental Factors Causing Stress and Damage
After ruling out watering issues, the next common causes of aloe distress relate to light exposure and temperature fluctuations. Aloe vera requires bright light to thrive, but too much intense sun can quickly damage the leaves, especially when the plant is moved abruptly from a shaded to a sunny location. Sunburn on aloe appears as distinct patches of reddish, orange, or hard, dry brown discoloration on the foliage.
If you observe these hard spots, immediately move the plant to a location that receives bright, indirect sunlight. The plant may still tolerate some direct morning sun, but intense, midday exposure should be avoided to prevent further scorching. While the sun-stressed leaves may not fully revert to their original green, the plant will recover and produce healthy new growth in the center.
Insufficient light causes a condition called etiolation, where the plant attempts to stretch itself toward a light source. Etiolated aloes display pale, weak, and elongated leaves with a thin, stretched appearance at the base. This stretching compromises the plant’s structural integrity and leaves it vulnerable to disease.
The solution to etiolation involves gradually increasing the plant’s light exposure, aiming for approximately six to eight hours of bright light daily. Sudden placement into intense sun should be avoided, as this will result in immediate sunburn on the weakened tissue. Cold temperatures also pose a threat, as the plant prefers a temperature range between 55°F and 80°F.
Exposure to temperatures below 50°F can cause cold damage, resulting in leaves that look soft, mushy, or “glassy,” often accompanied by black or dark brown spots. This discoloration is due to the freezing of water within the leaf cells, which causes them to rupture. If cold damage occurs, move the plant to a warmer location, trim away the fully collapsed or blackened tissue, and allow the remaining plant to dry out before resuming a regular care schedule.
Recognizing and Eliminating Common Aloe Pests
Although relatively pest-resistant, the Aloe vera plant can occasionally be targeted by sucking insects. The two most common pests are mealybugs and scale insects, both of which feed on the plant’s internal sap. A telltale sign of these infestations is the presence of “honeydew,” a clear, sticky residue on the leaves that can sometimes lead to black sooty mold.
Mealybugs are easily identified by their appearance as small, white, cottony masses, typically found clustered in the crevices where the leaves meet the stem. These soft-bodied insects are highly mobile in their immature stages, rapidly spreading across the plant if left unchecked. You can eliminate small clusters by dabbing them directly with a cotton swab soaked in 70% isopropyl alcohol, which dissolves their protective wax coating.
Scale insects present as small, immovable, hard, oval bumps that appear along the leaf surface and midrib. The adult scale forms a protective, shell-like covering, making them difficult to treat with simple sprays. Treatment involves physically scraping off the adult scales with a soft toothbrush or fingernail, followed by a targeted application of insecticidal soap or neem oil to eliminate the remaining young “crawlers.”
Regardless of the pest, isolating the infected plant is the first step to prevent the infestation from spreading to other houseplants. Regular inspection, especially of the tightest areas near the base of the leaves, is the best preventative measure. Consistent application of neem oil or insecticidal soap every seven to ten days may be necessary to interrupt the pest’s life cycle.