Fungus is a common lawn problem, although different types of fungus have different symptoms. Powdery mildew has a dusty white appearance on grass and plants, while "melting out" fungus kills large areas of grass. Red thread appears as brown patches, and brown patch manifests itself as wet, brown patches surrounded by gray rings. Dollar spot fungus is commonly recognized by yellow patches of dead grass.
Mix 1 tbsp. baking soda, 1 tbsp. vegetable oil and a drop of liquid dish detergent with 1 gallon of water in a spray bottle. Shake the fungicide mixture well and apply to the lawn every seven to 10 days.
Mix together 1 cup skim milk and 9 cups water, and apply with a spray bottle every other week. Use skim milk instead of full-fat milk to prevent foul odor and other diseases that will feed off milk.
The cornmeal you probably already have in your kitchen cabinet is an easy way to control lawn fungus. Purchase larger bags of cornmeal from local feed stores if you have large lawn areas to treat.
Apply 10 to 20 pounds of cornmeal per 1,000 square feet of lawn. Your lawn should show significant changes within three weeks, and you can reapply this remedy once a month. The cornmeal remedy works by attracting trichoderma fungus, which is harmless to your lawn but kills invading fungi.
Test your soil's pH levels. Your grass needs the right pH in order to get nutrients and grow healthy. The wrong pH levels make grass susceptible to diseases and unable to fight them off. Adjust pH levels by buying a bag of limestone from your local home and garden center. Choose finely ground limestone, as it corrects the soil pH faster than coarse grinds.
Allow the grass proper drainage, because sitting water is an open invitation to fungi. Also, water your lawn early in the morning to allow daylight to burn off extra moisture.
Create good air circulation around plants by spacing them apart. This also helps to prevent fungus and other diseases from spreading plant to plant through leaves that are touching.