Troubleshooting plant problems
1) Problem: Cactus turns red; scabs and blisters form.
Diagnoses: Too much light.
Solution: Move the cactus to a more screened area.

2) Problem: Cactus turns yellow; growth is stunted
Diagnoses: Not enough light.
Solution: Move the cactus to a well-lit area.

3) Problem:Cactus becomes soft/mushy; no visible growth; cactus turns orange or rust coloured.
Diagnoses: Orange rot or the root has rotted.
Solution: Slice the damaged section off. Repot the cactus in dry soil. Place the cactus in direct sunlight and do not water for a couple of weeks.

4) Problem: Cactus is soft/mushy, no visible growth; tiny holes/tunnels have formed, tissue is visibly damaged.
Diagnoses: Contaminated by mold/bugs/fungi.
Solution: Remove the cactus from the pot/soil. Slice the damaged section off and remove the bugs. Rinse the cactus and roots clear of soil and bugs. Spray with pyrethrins or diluted spirit. After 1-2 minutes rinse off and repot the cactus in dry soil.