Question
Hello
I dont know the type of cactus, its over 5ft tall, has a trunk with arms, the type that can be found in many garden centres.  I've had it for 5 years and during that time had some new growth. The lower part of the trunk and arms are withering and turning brown.  Its located near a window but not in direct sunlight.  Is there anything I can do to save it ?

Answer
Dear Caroline,

If the very bottom is dried up that means the roots are probably dead. The only way to save your plant will be to take a cutting and replant. Use new soil, a cactus mix type is best. After you make the cutting (make each piece about 2 feet long), let them "heal" for a couple of weeks prior to planting. Once planted, water only when the soil is dry. Be patient as it may take a month or more to root.

Hope this helps.

Sincerely,

Greg