Cutting Heights

Mowing height is probably the most important parameter of mowing. Turfgrasses, like other plants, must manufacture sugars through photosynthesis in the leaves if they are collectively to develop into a high quality lawn. Turfgrasses mowed at low heights have limited leaf area to sustain photosynthesis rates necessary to maintain good plant vigor.

In addition to leaf area, a direct relationship exists between the height of the turfgrass and the depth and total mass of the root system. Research with Kentucky bluegrass has shown that root growth was more than twice as great when the grass was mowed at a 2.0 inch height verses a 0.75 inch height. In general, a lawn mowed too short will have a shallow root system with little total root mass. The impact of shallow, weak root systems is most apparent during summer stress periods. When soil moisture becomes limiting, the closely mowed lawns usually exhibit stress first and the loss of turfgrass plants is more likely. Higher mowing heights during the summer period will keep soil temperatures cooler, preserve soil moisture and help maintain turfgrass quality. Recommended mowing heights of cool season turfgrasses cultured in Ohio include:

Turfgrass Species:	Mowing Height (in inches):
Fine Fescue	2 to 3
Tall Fescue	2 to 3
Perennial Ryegrass	2 to 3
Kentucky Bluegrass	2 to 3
Creeping Bentgrass	1/4 to 3/4

Turfgrass mowed at the recommended height will have deeper, stronger root systems.

Mowing height can play an important role in prevention of lawn weed establishment. Research has shown that higher mowing heights result in fewer weeds per unit area. This is due to higher grass providing more shading and competition to the weed seedlings during the initial establishment phases.