Question
Dear Greg:

I have a small indoor cactus on a window sill.  It has grown two long shoots, which look great but then start to die from the tip inwards.  What can I do to stop these shoots from dying?

I water only when the soil is dry, not more than once a week.  I don't know what kind of cactus it is.

Thanks for your help!  

Answer
Dear Diane,

Usually when a cactus dies from the tip inwards, the plant was somehow damaged at the tip. Is any of the plant black or have a fowl smell? If you can give me a description of the thorns and the body of the plant, I may be able to give you a better answer.

Thanks!

Greg