Don’t mow too often

A lawn mowed too short generally has a shallow root system, which means the grass will be stressed during hot, summer months.

The best height for most lawns is between 2 1/2 and 3 inches, experts say. After cutting — no more than one-third of the blade should be removed in a single mowing — pull several individual blades and measure them. During spring and fall, cooler periods, blades should measure about 2 1/2 inches long. In summer, set the mower higher so blades measure 3 inches.

Landscape contractors mow at set heights — often as short as 2 inches — because they are on tight schedules. Experts say homeowners should request that their landscapers mow to higher lengths, especially during the hot months. Also, make sure the mower blade is sharp. Have your hardware store sharpen it once in the spring, then once again in late summer. A sharp blade reduces stress on the lawn.

Mike Harmon, owner of MH Landscaping, an organic firm in East Hampton, N.Y., says mowing every week or five days also can cause stress. “The lawn doesn’t read a calendar,” he says.

In cool temperatures, when grass grows quickly, once a week might be OK. In warmer weather, when lawns can be stressed, once every 10 or 12 days might be necessary.