Question
I own a coral cactus and one day it was fine and looked like it did the day I bought it, and then boom the next day it was folded over and black as if it is dying. I havn't changed anything on how I take care of it. Right now I have a heat lamp over it to provide light and heat. I have been caring for the cactus for about 6 months now. What could this be? I use drinking water to water it, it is in a larger pot than what it came in but has nev er been an issue. the window it sits in faces east. We try to water it every four to five days.

Answer
Amanda,

Cactus do not have a lot of roots therefore they do not need large pots. The larger the pot the more water you give them when you water it to moisten all that soil then the poor plant can't use up all that moisture before you are coming back with a water pitcher again. They need to be kept in small pots in very sandy soil. It needs to be equal parts of potting soil and sand. They need to be in a very sunny south facing window with drapes and blinds open all day or they need a flourescent light no more than 12 inhes above the plant. A heat lamp will damage the plant with the heat and not provide the proper light spectrum. It should not be watered until it has been very dry for at least a week. It does not rain in the desert often.

Your problem indicates the cactus has been overwatered and it will not recuperate. I suggest that you find another one and keep it in a small pot and follow the above instructions. Good luck.

Darlene