birdboyhg, You sure it's mold and not soil salts? Is it crusty or hairy? It could also be from using clorinated water if it's crusty. If is is indeed mold what you can do is take and mix a 1/4 cup of baking soda to a quart of water and mix well. Then take and wipe hard surface with this mixture to remove mold. Sounds like you might be watering the plant or plants a little to much also if it's mold. This time of year most plants don't need as much water as with the other seasons of the year.