brown spots on Aloe Vera
Quick answer
If your Aloe Vera has brown spots, the most likely cause is: Aloe Vera brown spots result from root rot caused by excessive soil moisture, leading to water-soaked lesions (bilateral indentations on both leaf surfaces) that appear as 'pinched' tissue. Aloe's CAM photosynthesis tolerates drought but succumbs to Phytophthora-like rot in anaerobic wet soil. Terra cotta wicking promotes surface algae as a high-moisture bioindicator. Edema (corky brown lesions) from turgor pressure in overwatered succulents under low light/low evaporation conditions also causes brown spotting.
Start here:
- 1. Gently remove plant from pot to inspect roots; healthy roots are white and firm, rotted roots are black and mushy
- 2. Trim all blackened, mushy roots with sterilized shears; treat remaining roots with dilute hydrogen peroxide (1 part 3% H2O2 to 2 parts water)
Why Aloe Vera gets brown spots
Aloe vera
Aloe Vera brown spots result from root rot caused by excessive soil moisture, leading to water-soaked lesions (bilateral indentations on both leaf surfaces) that appear as 'pinched' tissue. Aloe's CAM photosynthesis tolerates drought but succumbs to Phytophthora-like rot in anaerobic wet soil. Terra cotta wicking promotes surface algae as a high-moisture bioindicator. Edema (corky brown lesions) from turgor pressure in overwatered succulents under low light/low evaporation conditions also causes brown spotting.
How to reverse brown spots on Aloe Vera
- 1
Gently remove plant from pot to inspect roots; healthy roots are white and firm, rotted roots are black and mushy
- 2
Trim all blackened, mushy roots with sterilized shears; treat remaining roots with dilute hydrogen peroxide (1 part 3% H2O2 to 2 parts water)
- 3
Repot in fresh well-aerated succulent/cactus mix (50% perlite/pumice) in a clean terra cotta pot
- 4
Water sparingly post-repot — only when top 2-3 inches of soil are bone-dry (every 2-3 weeks indoors)
- 5
Scrub algae from terra cotta pot with undiluted 3% hydrogen peroxide if reusing
Keep brown spots off this Aloe Vera
Switch to gritty, fast-draining succulent soil mixes with 50%+ inorganic perlite/pumice; water only after soil dries; ensure 6+ hours indirect light, 40-60% humidity max, and good airflow to prevent algae growth on pot surfaces.