Plant guide:ðŸŒĩ Cactus
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Fungal

Fungal Rot Spots on Cactus Skin

Commonly affects: Cactaceae (Cactus)

Circular, sunken, discoloured spots develop on the cactus body, sometimes with a soft or slightly fuzzy texture, distinct from the whole-plant collapse of basal rot.

Potential Causes

  1. 1Various fungal pathogens entering through wounds or areas of trapped moisture
  2. 2Water sitting in ribs or crevices after watering or rain
  3. 3Poor air circulation keeping the plant surface damp longer than necessary

Solution Steps

  1. 1Cut away affected tissue with a sterilised blade if the spot is limited and shallow
  2. 2Let the cut area callus and dry before any further watering
  3. 3Improve air circulation around the plant
  4. 4Avoid overhead watering that leaves water sitting on the plant's surface

Prevention Tip

Water at the base of the cactus rather than overhead, so water doesn't collect and linger in ribs or crevices where fungal spots start.

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