Suggested mowing heights
Fine fescue: 2.5 to 4 inches
Kentucky bluegrass: 1.75 to 3.5 inches
Perennial ryegrass: 1.75 to 3.0 inches
Tall fescue: 2.5 to 4 inches
Bermuda: 0.5 to 2.5 inches
Zoysia: 0.5 to 3 inches
Cooler season grasses ( rye, bluegrass fescue) can handle taller mowing heights while warm season grasses ( bermuda & zoysia) can be mowed shorter. Turf grasses grow at different rates depending on weather, type, location (sun vs shade) and fertilization.. The best practice is to remove no more than one-third of the grass blade at any one mowing.This "one third rule" will help maintain steady root growth. Removing more adds stress to the grass and may minimize root growth while the above ground are recovering and growing back. For cooler season transitional zone grasses, consider mowing taller than recommended height (half an inch) for times of added stress - the heat of summer or during long dry periods. Resume mowing at the regular height when the weather gets better.