How often should I mow my lawn in Virginia?

Mow by the grass, not by the calendar. Virginia Tech's guideline is to mow often enough that no more than one-third of the leaf height comes off at any one mowing.^[1] For a typical Virginia lawn, that works out to about every five to six days in active growth and every 10 days or less once growth slows.^[1] For many lawns that settles into roughly weekly mowing, with extra cuts in the spring and fall flush and fewer in a summer drought.

The one-third rule in practice

The rule is simple: never remove more than one-third of the leaf blade at any one mowing.^[4] Turn it into a number by multiplying your cutting height by one and a half. A lawn kept at 3 inches is due at about 4.5 inches; a lawn kept at 4 inches is due at about 6. For tall fescue, Henrico County's Extension office says to set the mower at 3 to 4 inches for fescue lawns,^[2] so most fescue lawns come due somewhere between 4.5 and 6 inches. Our guide to mowing height for fescue covers the height side.

A ruler stuck in the lawn twice a week in spring tells you more than any schedule. Once you see how fast your grass grows in a given month, you can set your mowing day around it.

How often through the Virginia year

Cool-season lawns (tall fescue, Kentucky bluegrass, perennial ryegrass, fine fescues) are most of Virginia's lawns. Cool-season grasses thrive when daytime highs are consistently in the 60 to 75°F range,^[3] which is why in Virginia cool-season lawns do their best growing in spring and fall, while warm-season lawns grow from mid-spring through mid-fall.^[3] In practice:

• Spring: growth takes off as the weather warms. Expect every five to six days at the peak, because tall fescue has a high mowing requirement during active growing periods.^[3]
• Summer: hot, dry weather slows fescue down. Weekly or longer is usually enough, and in a real drought the advice is to keep mowers and other traffic off the lawn during extreme drought.^[5]
• Fall: cooler nights and rain bring a second growth spurt. Mowing often goes back toward every five to six days, and the mower can chop fallen leaves at the same time.
• Winter: cool-season grass grows slowly; an occasional cut on a mild spell may be all it needs.

Warm-season lawns (bermudagrass, zoysiagrass, centipedegrass, St. Augustinegrass) follow the heat. Warm-season grasses are adapted to consistent temperatures in the 80 to 95°F range,^[3] so they need the most mowing in midsummer. Repeated frosts eventually put warm-season grasses into winter dormancy, with a loss of green color, for 4 to 5 months from late fall to early spring,^[3] and mowing stops.

How much care you want sets the pace

Frequency also depends on the lawn you are aiming for. Henrico County's SMART Lawns program describes mowing twice a week for a high-maintenance lawn, weekly for regular maintenance, and every 10 to 14 days for a reduced-maintenance lawn,^[2] with the higher-maintenance lawns also getting more water and fertilizer. That trade-off is worth knowing, because your own habits drive how fast the grass grows. In Virginia Tech's words, "Overwatered lawns frequently lead to excess blade growth, summer fungal diseases, and more frequent mowing."^[5] Henrico's guidance adds that fertilizing cool-season grasses in the fall builds roots without stimulating excessive growth,^[2] which also means fewer spring mowings.

Habits that make frequent mowing easier

• Mow dry grass. Wet grass sticks to the mower and falls in clumps on the lawn,^[1] so a rainy week can push mowing back a day or two. That is fine as long as you do not let the grass run far past the one-third mark.
• Catch up in stages. After a vacation or a wet spell, raise the deck, take off a third, and come back a few days later for the next cut.
• Mow new grass early. For a new tall fescue lawn kept at 2 inches, Virginia Tech's example is to "begin mowing as soon as your new lawn reaches a 3-inch height."^[4]
• Keep the blade sharp. More mowings mean more wear; a sharp blade cuts cleanly where a dull one tears. If the lawn browns after mowing, see why a lawn turns brown after mowing.

If you fall behind

Letting the grass go is not only a lawn problem. Under Virginia law, localities may require owners to cut grass and weeds, and after reasonable notice may have it cut by their own agents and charge the cost to the owner.^[7] Fairfax County, for example, runs a seasonal grass compliance program from April through October,^[6] and there, residential lots under one-half acre must keep grass under 12 inches.^[6] Rules differ by county, city and town, so check your own locality's code if you will be away for a stretch of the growing season.

Stop and call a pro if

• You cannot keep up with spring growth, or you will be away for weeks in the growing season.
• Parts of the lawn are too steep, wet or rough to mow safely with your equipment.
• The lawn browns or thins in patches even though you are mowing on schedule at the right height.
• Your locality has sent a tall-grass notice and you cannot cut it in time.

For more, see what lawn mowing costs in Virginia and what to look for in a mowing service, browse the lawn and landscaping answers, or look up lawn and landscaping businesses around Blacksburg. To have the lawn mowed on schedule, describe the job once and local businesses quote it.