Zoysia, like other warm-season grasses, goes dormant in the winter. Winter dormancy leaves many homeowners wondering, "Do I need to do anything to my Zoysia in the Winter?"
If you have an established Zoysia lawn you can let it go until Spring. Zoysia really is a low maintenance grass especially during the cold season. However, if you have plugs that are less than a year old you should water periodically. Normally one thorough watering (about an inch) biweekly should suffice while the plugs are dormant. This is dependent on rain/snow. Established Zoysia lawns do not require any watering over winter because their deep root system will have more access to moisture in the ground.
Dormant Zoysia will appear golden-brown in color. It should not turn white or gray.
Prior to dormancy you can mow the Zoysia at about 2 inches in height but do not scalp it. Do not mow, aerate or dethatch dormant Zoysia. Leaving the old growth and a light thatch layer will provide the zoysia plugs extra protection during frosty conditions. In early spring prior to green-up (March for most zones) you can mow the old growth low. After mowing rake off and dispose of the clippings. This will help to reduce the over-wintered thatch and will give the appearance that your Zoysia is greening up faster.
Make sure that you are ready to fertilize come Spring. As soon as your Zoysia is completely green you may apply fertilizer. You do not want to fertilize during the colder months as Zoysia roots do not grow in the Winter. Always be certain to follow the application instructions and do not over fertilize. Before you know it you will be back to enjoying your lush, green lawn!