Plant guide:ðŸŒĩ Cactus
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Roots

Root and Basal Rot in Cacti

Commonly affects: Cactaceae (Cactus)

The base of the cactus turns soft, dark, and mushy, sometimes with a foul smell, and the plant may topple or feel loose in its pot.

Potential Causes

  1. 1Overwatering, by far the most common cause of cactus decline
  2. 2Poorly-draining soil retaining too much moisture around roots
  3. 3Pots without adequate drainage holes

Solution Steps

  1. 1Remove the plant from its pot and cut away all soft, dark tissue with a sterilised blade, cutting back to firm, healthy tissue
  2. 2Let the cut surface callus (dry and form a protective layer) for several days before repotting
  3. 3Repot into a fast-draining cactus-specific mix with added grit or pumice
  4. 4Water far less frequently going forward, letting soil dry out completely between waterings

Prevention Tip

When in doubt, underwater a cactus rather than overwater — most cacti tolerate weeks of drought far better than a few days of soggy soil.

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