Question
Hi there....I have a Totem Pole cactus (Lophocereus schottii) cactus that I bought in AZ a few years ago and has been doing well here in Massachusetts.  It is an indoor plant about 2 feet tall and has started getting black on top. What is it and what can I do to save the plant.  The black is not due to a freeze, it has been indoors all winter.  Thanks!

Answer
Tony,

It would be best if I saw a picture. Can you send one to me at [email protected] ? If it wasn't the cold, then it is most likely too much water. That particular plant comes from a very arid region. Cut back on your watering and as long as the plant has not rotted internally, it should heal. Please send a picture if possible.

Sincerely,

Greg