It might also be powdery mildew - it is a problem with a lot of plants in humid weather and goodness knows it can get humid in Florida in the summer!
Here's a link that describes it:
http://www.uri.edu/ce/factsheets/she...erymildew.html
Here's one for mealy bugs:
http://www.mrec.ifas.ufl.edu/lso/mealybugs.htm
Check to see which you have and good luck! I've found mealy bugs much easier to treat than powdery mildew...