The Aloe vera plant is a familiar succulent, recognized for its hardiness. It stores a clear, soothing gel within its thick, fleshy leaves. Despite its reputation, a struggling aloe is common, usually signaling an easily corrected imbalance in its care routine. Most aloe problems are not fatal if diagnosed and treated promptly.
Saving Aloe from Water Stress and Root Rot
The most frequent cause of collapse in Aloe vera is overwatering, which leads to a fungal infection known as root rot. This occurs because the plant’s roots are adapted to dry conditions and quickly decay in perpetually saturated soil. The early symptoms of this silent decay are often subtle but progress to mushy, yellowing, or browning leaves that lose their firmness and may droop.
A plant suffering from advanced root rot may have a soft, unstable base, and the soil will often emit a foul, stagnant odor due to the decomposition process. To confirm the issue, the plant must be gently removed from its pot to inspect the root system. Healthy aloe roots are firm and typically light tan, yellow, or orange, while rotting roots are dark brown or black, slimy, and easily detach.
Use a sterile, sharp tool to prune away all compromised tissue, cutting back until only firm, healthy, white root or stem remains. If the entire root system is lost, the plant can still be saved by cutting the stem just above the rot. After trimming, the plant should be left in a shaded, well-ventilated area for several days to allow the cut surfaces to dry out and form a protective callus.
Callusing seals the open wound, preventing new infections when the plant is returned to soil. Once a dry, scab-like layer has formed, the aloe can be repotted into a clean container with new, well-draining succulent or cactus soil mix. The pot must have sufficient drainage holes, and watering should be withheld for at least a week or two after repotting to encourage new root growth.
Fixing Damage Caused by Light and Temperature
Aloe vera requires bright light, but too much direct, intense sun can cause a condition similar to sunburn. Damage manifests as a change in leaf color; the foliage turns red, orange, or brown, often with dry, shriveled tips. If sun stress is observed, the plant must be moved to an area that receives bright, indirect light. Relocation into stronger light must be done gradually over several weeks.
Conversely, an aloe that is not receiving enough light will exhibit signs of etiolation, or “legginess.” The leaves will appear thin, pale green, and elongated as they stretch noticeably toward the nearest light source. To correct this, the plant should be slowly introduced to a brighter spot, increasing its light exposure incrementally to prevent sudden sunburn. The stretched leaves will not revert to their compact shape, but the new growth should be healthy and stocky.
Temperature extremes threaten this tropical succulent, which requires a minimum nighttime temperature above 40 degrees Fahrenheit. Cold shock or freezing is devastating because the high water content of the leaves causes the cell walls to burst when the internal gel freezes. The damaged foliage will appear translucent, shriveled, or black and mushy.
If the plant has been frozen, it should be moved immediately to a stable, warm environment. All leaves that have turned black or have a glassy, translucent appearance must be trimmed away with a sterile tool, as this dead tissue will only encourage secondary rot. Recovery is possible only if the central core remains unfrozen, requiring minimal watering until new growth is confirmed.
Eliminating Common Aloe Pests
Even a healthy aloe can be susceptible to sap-sucking insects; mealybugs and scale are the most prevalent. Mealybugs are identified by the small, white, cottony masses they form, typically congregating in the crevices where the leaves meet the stem. These pests feed by piercing the plant tissue and extracting sap, which can weaken the aloe over time.
Scale insects are less obvious, appearing as small, hard, immobile brown or white bumps stuck to the leaves, often along the midrib. Both mealybugs and scale excrete a sticky substance called honeydew, which can lead to the development of sooty mold on the plant surface. The first step upon discovering an infestation is to isolate the plant immediately to prevent the spread of pests to other houseplants.
For treatment, a cotton swab or small brush dipped in 70% isopropyl alcohol can be used to manually touch and wipe away each individual pest or cottony mass. The alcohol desiccates the soft-bodied insects, and this method allows for precise application without soaking the plant with excess moisture. Small, localized populations can also be dislodged with a strong jet of water.
For more extensive infestations or for inaccessible areas, a horticultural oil or insecticidal soap can be applied, ensuring thorough coverage of all leaf surfaces. Following successful treatment, the plant should remain quarantined for several weeks to monitor for any new pest outbreaks before being returned to its original location.