Fescue grass needs mowing only when it exceeds its recommended lawn height of 3 inches. Wait until the grass is 4 inches tall and then take off 1 inch. During the growth spurts in the spring and fall, fescue needs mowing every five days. During the winter, it may not grow due to cold weather.
Only take off one-third of the fescue grass blade's height when cutting. If the fescue grass is overgrown, it is better to do several cuttings to bring the grass down to the proper level.
Do not cut fescue grass below 1 1/2 inches tall and do not mow the grass while wet. This damages the grass blades and clogs the lawnmower. If you have to cut the grass in the winter because the mild weather allows the fescue to grow, make sure the grass is dry before mowing.