Monterey Complete Disease Control is an effective tool against plant diseases. We have used this for years and find it works. Use on houseplants, tropicals, flowering plants, shrubs, fruits, ornamentals and vegetables. Spray susceptible plants before you spot disease, like on tomatoes in cool, wet weather. Continue to spray weekly and it will kill spores as it dries on leaf surfaces. It is a Biofungicide/Bacteriacide approved for organic gardening.