Thanks for the advice, Chuck. I had previously been watering the leaves twice a day and I suspect that that contributed to my developing the mold to begin with. This is my second year as a tomato grower and I'm definitely "learning by doing". It's really great to be able to get info from people like you who grow hundreds of plants. I was watering the leaves upon advice from a neighbor and I just realized that the neighbor's tomatoes died of wilt both years... Margaret, Thanks for the link to Extoxnet. I feel better about using the product now. --Michael