Question
My Dracaena Fragrans, which I keep indoors and is 6 feet tall and in perfect condition, has suddenly developed a very strong "moldy" smell. What is so strange is that it is NOT coming from the dirt, which I water every 10 days and let it completely dry out before watering again, but from the inside of only one stalk. The plant has two very large stalks and the one that smells so badly has also got several round holes in the new growth. I did not notice these holes until I put the plant out on the porch. Yes, it is smelling up the house that bad. What could it possibly be?

Answer
Lynda,

My guess is that some type of insect chewed on the plant and made a wound.  The insect probably found the plant when you placed it outside.  As a result, I sounds like a soft rot bacteria or a mold has invaded the wounded area.  

Soft rot bacteria often smell bad and will make the stem/leaves softer than normal.  Sometimes there will be a water soaked appearance.  If it is a mold, it will often have a musty odor.  The mold may not be a true pathogen that causes a problem to the plant, but is taking advantage of the wound.  Usually molds will produce visible fungal growth and spores when humidity is high.  For this reason, they can make people with mold allergies sneeze, have a runny nose or other hay fever type responses.

I might suggest that you prune off the affected stem.  Hopefully, this will prevent the problem from invading the normal stem.  While the plant is recovering from pruning, keep the plant dry (no rain or irrigation on the foliage) which reduces the likelihood that a fungus/bacteria will invade.

Good luck!
-Jen