Question
Hi, my mom got a large cactus  about 5' high, several years ago.  I don't know the exact name, but it is the one most thought of that is tall with 2 arms.  Her cactus has done fine until recently when she saw a lot of dust on it and decided to polish it.  About three months ago she used a little bit of mayonnaise to do so.  She has done this with all of her other plants and cactuses with no problems.  Now the cactus is turning brown and dying.  We are wondering if the mayo is what would have caused this.  (If it helps she lives in Wyoming.)  Thanks!

Answer
Dear Crystal,

I wouldn't think that would be the issue and it may be just a coincidence. However, if the plant turned brown everywhere all at once it might have been. If the plant turned brown from the bottom up or the top down, there was something else at work.

Bottom up means rot usually from over watering and top down usually means root damage (lack of water). Hope this helps.

Sincerely,

Greg