Here’s an easy organic spray “recipe” to prevent black spot, powdery mildew, and other fungal diseases in your garden.

Unlike some home remedy recipes, this one actually has university research behind it to demonstrate that it works. I feel it’s not as effective as commercial chemical fungicides, but it definitely reduces fungal diseases.

Here’s how to make it and use it:

Mix together 2 tablespoons baking soda, 1 tablespoon liquid soap, and 2 quarts water. Use a large spray bottle if you have just a few plants; invest in a small landscape sprayer if you have dozens of plants to do.

Spray plants in the early spring, just a few weeks after they start active growth. Whenever the lilacs start to leaf out significantly is a good time to start. It’s critical to spray them (both with organic and chemical sprays) well before the problem is apparent. (Fungal diseases usually start showing up on plants in mid- to late summer.)

Repeat the spray at least three times, about 10 days apart. This should be accomplished before daytime highs regularly hit 80 degrees.

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