Welcome Spring! And with it, grass mowing season.
First, determine the type of grass you have. Mowing guidelines are specific for different types.
Tall Fescue Mow 2 to 3.5 in the Spring, then 3 to 4 in the Summer and 2 to 3.5 in the Fall.
Bluegrass or other shade grasses 2 to 2.5 in the Spring, then 2.5 to 3.5 in the Summer and 2 to 2.5 in the Fall.
Bermuda and Zoysia Warm season grasses can be mowed at about 3 inches anytime. They should be de-thatched in the Spring before they begin to green up and grow.
Mowing times should be consistent and grass should not be allowed to get so high that more than one third of the grass is removed when you mow. Higher mowing helps promote deeper root systems, thicker grass, and less maintenance. Spring is a good time to sharpen or replace the mower blades.
Reference: University of Missouri Extension program “Healthy Yards for Clean Streams”