My Cactus Offshoots are Wilting

Taking Offshoots

• Cut offshoots off the parent plant with a sterile sharp knife at the soil line. Lay the piece of cactus out on the counter for up to two weeks to callus and form a dry white crust on the cut edge. This helps prevent rot and promote rooting. Cacti need well-drained, gritty soil, so a mixture of 2 parts peat moss and 2 parts sand makes an ideal medium. You can also purchase a cactus mixture. Insert the callused end of the offset into the planting medium and put it in a warm location with indirect bright light.

Fungal Soft Rot

• Fungal soft rot is a disease common to newly planted offsets. It begins at the cut area or callus and progresses to affect the entire tissue. This happens when the cut end is introduced to a medium with fungal spores in it and the exposed end gets infected by them and rots. Fungal diseases can be prevented by using soil-less or sterile media and by dipping the cut end into a sulfur fungicide.

Root Mealy Bug

• Root mealy bug is found in the soil of the cactus. It's usually contracted from a purchased plant or infested soil. The insects will eat the roots of the offset even as it forms them. This prevents it from getting any nutrients and moisture, and eventually it will die. The decline will be slow and may include wrinkled skin, softening tissue and discoloration. The only cure is to wash the roots with methylagted spirits and then rinse them. The soil has to be thrown out and the pot sterilized.

Nematodes

• Nematodes are tiny organisms that live in soil. The worm-like pests are responsible for the pale and stunted growth of offshoots. They burrow in around the roots and colonize them, which damages the roots. The plant will slowly fail. The soil needs to be changed, and the roots need to be rinsed and checked for damage. All the discolored parts of the roots have to be cut off -- and then the plant should be allowed to dry on a counter for a week. Repot with a sterile potting mix. Future outbreaks can be combated with a systemic insecticide, but be cautious as some cacti are sensitive to chemicals.