I have sprayed my plants for years, one word of caution though, Be sure to raise your Lights way up out of the line of fire. If you hit a Hot bulb with water, it can and will explode!! one reason I have sprayed in the past is Gnats, I take 1 clove of garlic, about 10-15 whole cloves (yes Cloves) like you use on a Ham, and about an ounce of Dawn dish soap. you boil this in a medium size pan on a low boil for ten- fifteen minutes, let it cool, strain, and pour into a spray bottle. The little fuckin Gnats Hate the shit!! I spray the soil too, works for ALL kinds of insects, and doesn't harm your plants+ washes away when you spray your plants with plain water.. Just my 3 cents worth, works for me and I have Never had a Mold/fungus problem...
Pilgrim