Proper mowing height is important in maintaining the health and overall appearance of your yard. Each kind of turfgrass has its own recommended upper and lower mowing height. It's very important to stay within these recommended mowing heights (see the table).

Mowing at the lower end will often result in an increase in the growth of the stolons and rhizomes, resulting in increased turf density and thickness. However, lower mowing reduces the amount of leaf area, which decreases photosynthesis, and the root mass will usually be decreased. This can reduce the tolerance to foot traffic, as well as heat and water stress, resulting in a brown lawn. Lower mowing is tolerated better during the summer months in Hawai'i when our warm season grasses are at their highest growth rate. Very low mowing of ‹ to ⁄ inch should be restricted to golf greens and tee boxes, where special professional care and equipment is required.

Raise the height a little during the winter months when the growth rate is much slower. Even a small increase in height can produce significant benefits by allowing more leaf area, which results in deeper roots and higher stress resistance. However, mowing at or above the upper end of the range often results in a loose, tufty appearance and a rapid growth of the thatch, giving the lawn a spongy feel that will lead to scalping.

The actual mowing height you use should depend on how often you mow, the mowing height tolerance of your particular type of grass, and its location. In shaded areas, for example, raise the mowing height by 30 to 50 percent to compensate for the elongation of the leaf blades under low light. Home lawns should not be cut lower than 1/2 inch.

A second consideration is selection of mower. The mowing tolerance of your individual turf species will be the main factor in determining the type of mower to use. The two basic types of power mowers used by homeowners are the reel and rotary mowers.

A reel mower is best to use on lawns cut at one inch or less. A reel mower cuts with a shearing action as multiple blades (seven to 11) turn against a stationary bed knife. The reel mower produces a better lawn appearance when the blades are kept sharp and aligned with the bed knife. Reel mowers have disadvantages in that they are more expensive to purchase, more difficult to maintain in good working condition, not very maneuverable around corners and in tight places and on uneven terrain. They do best on relatively open level lawns cut at under one inch.

Rotary mowers should be used on lawns cut at one inch or higher. A well-designed rotary mower lifts the grass by creating a suction and gives a uniform crew-cut type look. A mulching rotary mower keeps the clippings in suspension long enough to re-cut them several times and discharge them directly down into the thatch. The blade must be kept sharp because as the rotary blade becomes dull it tends to produce a frayed leaf edge that dries out, giving a brown or yellow cast to the lawn. Rotary mowers are less expensive than reel mowers and are far more versatile. They handle weeds and thick grass with ease and are much more maneuverable.

Mow often enough so that you do not remove more than a third of the leaf growth at a time; the lower the cutting height, the more often you will mow. If you follow the recommended mowing frequency, clippings should not cause a problem and should be left on the lawn. This will recycle many of the nutrients that would otherwise be lost if clippings are bagged. As much as 50 percent of the nitrogen fertilizer you put onto the lawn can be retained in this manner.