Lawn fungus is a common problem for homeowners. Fungus can take many forms, including unsightly brown patches in your lawn. You may lose only a few sections of turf to fungus, or your whole lawn may be affected. While you can apply a fungicide after the fact, it takes a while for the lawn to recover and look healthy again. Prevention is a better way to insure your lawn remains as green and healthy looking as possible, all season long.
Apply a fertilizer that contains fungicide in the spring and in the fall. Pestproducts.com recommends using one that contains a systemic fungicide, as these are preventative.
Avoid applying high nitrogen fertilizers to your lawn if you suspect it is vulnerable to fungus or may have a fungus. According to pestproducts.com, high nitrogen fertilizers
promote fungal growth.
Water your lawn in the morning--not at night. Moisture left on the grass overnight evaporates too slowly, allowing a damp environment favorable to fungal spores. Servicemagic.com recommends investing in a sprinkler system, with a timer, if your schedule won't permit morning watering.
Practice good lawn hygiene. Keep the lawn free of decaying yard debris and excess thatch. Raking your yard occasionally will help keep thatch from forming and remove
organic debris. Many lawns also benefit from aeration--you can rent lawn aerators from many garden centers and home improvement stores. Aerators help break up excessive thatch and compacted soil.
Mow properly. Keep mower blades sharp and do not mow grass when it is wet. In addition, gardening.cornell.edu suggests keeping your lawn at the maximum height--don't mow it shorter than you need to for the variety of grass in your lawn.