Guest Author - Connie Krochmal
Though cacti and succulents have fewer problems than other plants, life isnít always a bed of roses. Some of the most common problems can be avoided if the plants receive proper care. Letís look at specific situations that can occur.
Rots can occur at various locations on the plants. The most typical would be stem rot, crown rotóalso known as neck rotóand root rot. The latter isnít seen until the problem is pretty advanced. By that point, the rest of the plant has become waterlogged, discolored, and soft. In such cases of root rot, there is little one can do to save the plant when the damage is clearly so pronounced. If this happens to clumping species, check all the smaller offsets to see whether any are still healthy enough to try to save.
Neck rot starts at the base of the plant. The area loses its healthy green color and becomes dark brown or otherwise discolored. The affected tissue will be soggy to the touch, shiny, and finally rotten. By the time you realize the problem is prevalent, it isnít really possible to save the bottom part of the plant. Depending on the species and the extent of the damage, you can often salvage the upper portion by cutting it off and rerooting it. If you do this, be sure that you cut well above the damaged area.
Now the good news is that rots of all sorts can often be prevented for most indoor cacti and succulents. Avoid overwatering for this can create prime conditions for rots. Donít splash water on the bodies of the plants. Reduce water during the plantís rest period. Also, provide the proper temperature levels for that particular cacti or succulent.
Corky spots can occur on any part of the stems or branches of cacti and succulents. This most often happens on cacti. As the name implies, the spots are brown like cork. As a response to some form of stress, the plant creates layer upon layer of tissue to seal off the damaged area. This gives the spot a rough, irregular texture.
If the corky spot occurs on the upper portion of a stem or joint, the damaged tissue can be pruned. An example might be one joint or pad of a prickly pear. On cacti or succulents that are composed of one segment, stem, or body, this isnít possible. If the damage is very limited, the plant is worth saving. Otherwise, I would throw it out.
This disorder can be minimized by watering and fertilizing properly. Good air circulation is a must, especially for desert cacti for these originated in a dry climate with a low humidity.