Knowing When To Mow and Proper Height.

Mowing turf at the proper height is vital to lawn health, but ideal height varies based on grass type, time of year, and growing conditions. Grass requires more frequent mowing during its peak growth period.

The most important mowing rule is never to remove more than one-third of the leaf surface at any one mowing. In other words, determine the ideal height for your grass and allow grass to grow one-third higher. To set mower height, place it on a flat surface and measure the distance from the ground to the blade.

For cool-season turf, such as fescue or Kentucky bluegrass, active growth occurs during spring and fall. Typical cool-season grass height range: 2.5–4 inches.

For warm-season grasses, including zoysia and Bermudagrass, peak growth occurs during summer. Typical warm-season grass height range: 1–3 inches.

During periods of peak growth, expect to mow grass once every 5–7 days. Conversely, during times of slowest growth, you’ll mow less, if at all.

Follow these general guidelines for grass height. Determine regionally specific heights – and suggested seasonal variations – by contacting local extension offices or sod or seed suppliers.

Grass Type General Grass Height (inches)
Cool-season grasses
Fine fescue 0.5–3
Kentucky bluegrass 0.75–3.5
Perennial ryegrass 0.75–2.5
Tall fescue 1.5–4

Warm-season grasses
Bermudagrass 0.5–2.5
Buffalograss 1.5–4
Kikuyu grass 1–1.5
St. Augustinegrass 3.5–5.5