Look out.. Brown Patch is back and here to stay as long as we have wet weather and large temperature swings. All grass is prone to brown patch, but is mostly seen in St. Augustine grass. If you have St. Augustine this is something you need to be aware of! Brown Patch does not need to go ignored. The fungus can spread throughout the lawn in what seems like overnight. Apply a fungicide as soon as possible to stop any further spread. Moving forward, make sure to allow your lawn enough time to dry out before watering to reduce moisture.