Question
I have some white mould growing on the side and underneath the new leaves.
What can I do?

Answer
Hello Michele,

If it really is mold growing on your phalaenopsis leafs, you can try mixing a few drops of mild dish soap in a cup of warm water and using a soft cloth or paper towel, wipe the affected leafs.  The mold should come off.  But, if it is what I think it is, when you look at the cloth you may find tiny insect bodies on it.  If there are, what you have is a mealybug infestation!  Mealybugs are not something you want on your phalaenopsis orchid as they will slowly suck the life out of your orchid.  

To get rid of mealybugs, go to your local garden center and ask for a systemic insecticide recommended for orchids.  Mix according to the directions and water with it.  It will take three applications over three weeks to make sure you've gotten all of them, including any eggs that may hatch after the first application.  It would be a good idea to do this again in the fall to get any newcomers.  

Hope this helped.  

Jim Kawasaki
San Jose, Ca.