- Crisp / dry leaves - Sunburn (not applicable to old leaf die-off)
- Curling leaves - Underwatering and/or too much sun
- Discolouration from green to brown/red (whole plant) - Sun exposure (normal)
- Leaves appear pale green at the center and plant leans to the side - Too little light (Aloe version of elongation)
- Parts turn hard white/beige - Physical damage (hail, dogs, insects etc.)
- Burst or torn leaves - Too much water in a short period
- Leaf spots / fungal infection
- Aloe rust
- Uromyces aloes
- Stem rot / fungal infection
- Pythium ultimo
- Root rot / fungal infection
- Rhizoctonia solani
- Phytophthora nicotine var parasitic
- Phythium ultimum
- Sclerotium rolfsii
- Soft rot / bacterial rot
- Erwinia chrysanthemi
- Cause: Physical (hale, sunburn, spade/dog) or pest damage (snout beetle)
- Treatment: Newly bought aloes should be gradually exposed to sunlight. Place it back in indirect light and give it slightly more light over a period of 2 weeks. Scars cannot be treated and will remain on the plant until the leaf dies. Do not remove the leaf as this poses a higher risk for fungal infection. Treat secondary fungal infections (see Diseases).
- Cause: Too much water in a short period of time. (Either abnormally high rainfall or overwatering).
- Treatment: Let the leaves dry or remove affected leaves. Plant in a grittier, rocky mix to stop it from happening again. Place powdered sulfur on exposed regions.
- Causes: Overwatering, or watering from above.
- Treatment: Cut away dead tissue and dust with an anti-fungal powder. Keep the remaining pieces as dry as possible until the area scars/calluses over. A healthy stem might produce new heads once placed in adequate soil. Adjust watering practices.
- Cause: High temperatures and stressed plants exposed to fungi/bacteria (Fusarium /Dickeya) infection.
- Treatment: Unlikely, as the bacterial infection would have spread rapidly. You could try removing dead tissue, applying sulfur to exposed areas and letting the plant callus before watering again.
- Cause: Pythium ultimum, which flourishes in wet clay soil at temperature < 20 C.
- Treatment: The stem can be washed, dried and placed on new soil to root. Remember to use aerated soil with adequate drainage.
- Cause: Overwatering, not enough aeration in the soil or a beetle larvae/mealybug infestation that exposed roots to fungus.
- Treatment: Remove dead tissue, wash remaining plant and dust with powder fungicide. Let it dry for a period of 7-10 days before placing in new soil to root. Discard old soil.
Rootrot😨😱 Weeklong rain forecast for Cape Town next week. I recently got a hold of this little one & while repotting out of a waterlogged pot came across a prime example of rootrot. It is hard to spot. Easy to fix though. - Remove the plant - ID any limp and soft roots and remove as much of the dead tissue as possible. - Dip roots in a mix of 2ml sunlight 1L roomtemp water (to limit further infection) - Blot on tissue paper - Repot in dry soil and wait at least a week before watering again. Depending on the plant, you can wait even longer so new roots may sprout. #winter #rain #succulents #rootrot #AloeTrouble #AloePestsandDiseases
- Cause: Overwatering, lack of airflow and/or insufficient light causes fungal infections to develop. In some cases, insect predation or damage encourages fungal infection.
- Treatment: Improve planting conditions by moving it to a sunnier area with better airflow. Apply fungicide to affected areas or remove affected leaves and let wounds callus (dry and scar over). Citrus seed extract / Copper oxychloride spray (fungicide) application will help affected leaves.
- Beware: Aloe vera treated with a fungicide should not be used for household purposes.
- Cause: Temperatures of 25 C and high humidity (stops at temp >34 C) in other words aloes planted in shaded areas or between lots of plants.
- Treatment: Better placement in terms of sun and airflow. Minimize spreading by covering area with wet tissue paper, trapping spores, prior to leaf removal. Treat the infection with cinnamon or a sulfur-based fungicide.
- Cause: Fungus (Uromyces aloes)
- Treatment: Affected leaves need to be removed carefully. The concentric circles are fungal hyphae that present spores outside the leaves. Any disturbance (via a spray or similar vibrations) will result in the spores becoming airborne and affecting more plants. To stop the spores from becoming airborne, cover the affected area in wet tissue paper, cut the leaf and discard affected leaves in closed bags. Treat cut sites with a powder fungicide.
- Aloes known to be affected: Aloe baumii, A. glauca, A. maculata, A. saponaria, A. greatleadii, A. inyangensis, A. spicata, A. polyphylla, A. abyssinica, A. thraskii and A. littorals.
- Cause: Temperature 25-35 C, high humidity, waterlogged soil and excess nitrogen fertilizer, enters through damaged leaves.
- Treatment: Prevention rather than cure. Avoid excess fertilizer, overwatering or watering from above and damage to foliage. Saving an infested plant tends to be unpractical, but you can try and remove infected tissues whilst removing and replanting in a sunnier location.
Promise its not painted😱 This is a severe case of White scale infection I saw a few weeks ago. Left unattented it kills the aloe. The 2nd photo is a combination of fungus (dark spots) and scale. The dual contamination often happens to a weakened plant. Fungus thrives in mild wet temp like we are currently experiencing. If the plant receives sunlight and dries out then the infection will likely not spread. Removing fungal infected leaves are for the best as some fungicides do not kill spores. If the infestation is not too bad you can spray them with....you guessed it: sunlight in water. Photo 3 is a rescue aloe treated a few days ago. It will take multiple applications though. #winter #aloe #insects #AloeTrouble #LocalPests #AloePestsAndDiseases
- Cause: Sub-optimal growth conditions
- Treatment: You can treat it with a pesticide, however, the dead scales will still cling to the plant. You will have to physically wipe every leaf to remove the dead scales.
- Treatment: Physically remove snout beetles or spray pesticide.
- Treatment: There are some biocontrol agents and chromatic traps available to curb whiteflies.
- Treatment: Physically remove.
- Treatment: Remove with a hose, use a biocontrol agent like Aphidend (www.koppert.co.za) or apply an insecticide.
- Treatment: Most will advise you to discard the plant. The only remedy is to sterilize an implement (with surgical spirits) and cut away the affected area. Do not be conservative and make sure to remove everything. Do not let the infected tissue touch any other aloes.