Brown Spots on aloe vera
What's Happening
Brown spots on Aloe vera leaves develop from cellular rupture due to moisture imbalances. Water-soaked indentations appearing on both leaf surfaces indicate edema—turgor pressure buildup from overwatering combined with low evaporation rates. When soil remains moist for 7+ days in low-light conditions, root uptake exceeds leaf transpiration, causing cells to burst and create corky brown lesions. Secondary fungal colonization (manifesting as dark spots with yellow halos) occurs when humidity exceeds 60% with poor airflow. Unlike pest damage (which creates stippled patterns) or sunburn (which affects exposed surfaces), edema spots are bilateral indentations that feel sunken to touch.
How to Fix It
- 1
Inspect leaf texture: Bilateral water-soaked indentations confirm edema; raised bumps suggest scale insects; stippling indicates thrips
- 2
Unpot and examine roots: Trim any black/mushy roots with sterilized scissors; treat cut ends with cinnamon or 3% hydrogen peroxide
- 3
Repot in gritty succulent mix: Blend 50% perlite or pumice with cactus soil to maximize drainage; avoid moisture-retentive organic compost
- 4
Relocate to brighter indirect light: Position within 3 feet of east/south-facing window to increase transpiration and evaporation
- 5
Adjust watering protocol: Water only when top 2-3 inches of soil are bone-dry; use pot weight test—lift pot to gauge moisture content
How to Prevent It
Water only when soil is completely dry to the touch at 2-3 inches depth. Maintain bright indirect light (2000+ lux) to promote healthy transpiration. Use terracotta pots which wick excess moisture through porous walls. Ensure humidity stays below 60% with good air circulation to prevent fungal spore germination.