Although rare, common causes for brown patches to form in an otherwise healthy lawn are a thatch buildup, fungus, disease or an insect problem. All of these problems can be solved with a little effort.
A thatch build up can cause the grass to start dying, turning brown in color, allowing other weeds, fungus and grasses to invade your zoysia lawn. To correct the build up you would need to use a dethatching machine or vigorously rake the thatch out. Only do this when the grass is actively growing. For an easier solution a product such as our “Liquid Thatch Remover” can be sprayed on the lawn to rid and prevent a thatch build up.
There are many different types of fungus and disease that can affect the grass. If you suspect any of these it is very important to treat the area right away. Most fungus and disease are caused by thatch buildup, over fertilizing, hot humid temperatures, poor drainage and circulation. Correcting these conditions and if necessary the application of a fungicide can eliminate most fungus and disease. We do carry an organic fungicide, NPP Broad Spectrum Fungicide. If you are not sure you have a fungus or disease in your lawn it would be best to take a sample to your local garden center.
Some insects that live in the soil will eat the roots of lawn grasses. These insects are grubs, chinch bugs, nematodes and mole crickets. An infestation of these insects will cause the grass to die and turn brown. The use of an insecticide would need to be applied. Be sure to check the label and verify that what you are using will kill these types of insects not all insecticides will.
These are some of the most common causes of brown patches in your lawn.