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Powdery mildew is a serious plant disease that you can conquer organically with a simple, nontoxic solution of milk and water.

Brazilian scientist Wagner Bettiol was looking for a cheap way to control powdery mildew when he discovered that weekly sprays of milk controlled the growth of powdery mildew in zucchini just as effectively as toxic fungicides such as fenarimol or benomyl. And not only that, the milk spray boosted the plants' immune systems.

For decades, organic gardeners have been relying on a somewhat cumbersome spray of baking soda combined with a sticking agent?like oil or soap?to fight powdery mildew without poison. But Bettiol found that the super-easy concoction of nine parts water to one part milk slashed the severity of powdery mildew infection by 90 percent.