Question
I have a philodendron in my office at work.  Some leaves are beginning to have something like a white fungus on them.  I can wipe it off but it returns.  I know these are tropical plants. In the mornings it is very cool in my office from the air conditioning.  But once the door is opened it warms up.  Could the cool air have something to do with it?

Thanks for your help.

Answer
Kathy,

Is the plant also very damp? Cold usually doesn't encourage fungus growth but wet does. Also sitting where the air is still. Drain the plant as much as possible then kep it on the dry side. Let it dry out totally between waterings. To kill the fungus spray it twice a day for a week with Lysol spray or one of it's generic equivalants. Make sure you get the fronts and backs of all the leaves. The second week spray it once a day. After that spray it once or twice a week for awhile. You have to be consistant to kill any fungus spores that that keep reoccuring for awhile. It sounds like it may be powdery mildew which attacks a lot of plants outdoors this time of year so it is in the air and if your plant is overwatered it is susceptible. Philodendron likes to get very dry between waterings for a few days so it's roots have a chance to breath.  Good luck.

                                       Darlene