How to Prevent Fungus on Squash Plants

Fungus is a common pest for squash plants and other garden favorites like pumpkins and cucumbers. It most often appears as powdery mold or mildew, a white patchy mold on the plant's leaves. This disease begins with small white dots on a leaf or two, and progresses until the entire leaf is covered and dies. There are a few things you can do to avoid getting powdery mold. If your crops do get the mold, you can treat it with a simple inexpensive home remedy. The key to saving your crops is prevention coupled with diligence in treatment.

Quality seeds

Spray bottle

Plant good seeds. Choose well known and trusted seed distributors who have a good reputation. Avoid cheap seeds or ones that were packaged for previous seasons.

Plant the squash seeds the recommended distance from one another, usually about four or five seeds per hill. Planting too closely can harbor the disease and make it easier to spread from one leaf to another if it begins. Think about the habitat that mold and mildew likes to grow in. It enjoys dark, damp spaces, so when plants get overcrowded, it makes an attractive environment for fungus to grow.

Avoid planting in areas with weeds or much overgrowth. The fungus often can be carried by brush or weeds, and be passed on to your squash or other plants. Standing water also harbors disease, so avoid areas with poor drainage as well.

Pick out and eliminate the weakest plants once they sprout, and leave only the strongest two or three on the hill.

Fill a squirt bottle with soapy water. Use 2 to 3 tbsp. of soap per gallon of water. Antibacterial soap works best.

Spray any infected leaves with a generous amount of soapy water. It is best to do this in the late afternoon when the sun will not be beating down on the mixture, frying the leaves. Allow the water to dry on the leaves.

Use a garden hose to spray down the leaves and rinse the dried soapy water off. Repeat this process on a daily basis, as necessary.

Remove leaves from the vine that have died as a result of the infection. These are untreatable and can spread the fungus to your healthy leaves.

You can also treat fungus using milk or baking soda mixtures. Mix one part skim milk with two parts water, or 1 tbsp. baking soda with a gallon of water. Proceed as above.

Use a fungicide if the fungal infection is severe or does not respond well to treatment.