When dealing with fungus such as mold or mildew in your home kitchen or bath, use white vinegar to kill it and clean it away. If problem fungus shows up on your lawn, vinegar can also help get rid of it there.
Fungus growing on your lawn comes in a variety of colors and appearances. Powdery mildew is white and makes your lawn look as through you've sprinkled it with confectioner's sugar. Red thread fungus makes grass appear pink from a distance. Lawn fungus often shows up on grass that is poorly nourished and vulnerable to disease. The fungus rarely kills grass but it steals nutrients from it, causing it to turn yellow and thin out.
Vinegar contains acetic acid, which is strong enough to damage and kill fungus. Unfortunately, it is also strong enough to hurt grass in a lawn already weakened by fungal infection. To avoid doing more damage to your lawn, use vinegar in combination with other ingredients to make a spray to kill lawn fungus. Combine 2 tbsp. vinegar, 3 tbsp. hydrogen peroxide and 3 tbsp. baking powder with 2 qt. water. Mix them thoroughly in a plastic spray bottle.
Spray the vinegar-containing solution on lawn fungus, coating the visible mold or mildew. Next, spray a border of healthy grass about an inch wide around the infected area. This helps prevent the fungus from spreading. Reapply the spray every 10 days. If your area is receiving a lot of rain, increase the frequency of application to every five days. Continue to spray the protective border every time you use the mixture.
This spray retains its effectiveness for about three months; after that it loses potency and should be discarded. For best results, combine using the vinegar solution with cultural controls. Keep the grass trimmed short and rake away all thatch and debris, such as fallen leaves. If using the vinegar spray does not clear up the infection in a month, consider tearing out that portion of the lawn and replacing it with new sod.