Mowing has a major impact on lawn appearance and health yet is often overlooked in terms of importance. If you maintain your own yard, or hire someone to do it, here are a few simple guidelines to assure lawns are being mowed properly.
One very common mistake is mowing lawns too short. For most lawns, a mowing height between 2 1/2 to three inches is suggested; the upper range is best for summer. Piles of clippings and weed invasion indicates a lawn is mowed improperly. Lawns mowed at higher heights have deeper roots, fewer weed problems and look much better.
Mowing too close invites problems such as weed invasions. Simply raising the mowing height can have a major impact on the quality of many home lawns. A height of two inches is fine when grasses are rapidly growing, but the height should be raised as growth slows, stress increases and when the lawn is in shade.
Lawns should be mowed according to the rate of grass growth; remember not to remove more than one-third of the height. Mowing as the lawn needs it is essential. In the spring, this will likely mean more than once a week. It is never advisable to mow when the grass is wet.
Another issue related to mowing is whether clippings should be collected. As long as the lawn is mowed on an as-needed basis and the one-third rule is followed, clippings will readily filter back down into the lawn, and need not to be collected. The clippings readily decompose (they contain 75-80 percent water) and do not cause thatch. Clippings also recycle nutrients, especially nitrogen, so less fertilizer is needed.
The newer mulching mowers create even finer clippings, recycling the nutrients more often as the smaller clippings decay faster. Mulching mowers do not perform at peak efficiency if the lawn is too tall (removing more than one-third of the grass blade) or if the lawn is wet. If you do not use a mulching mower, don’t despair. A study at the University of Illinois showed mulching mowers did not provide any additional benefit over conventional rotary mowers. Cutting the grass at recommended heights and in a timely fashion is more important.
Another critical area often overlooked by homeowners is maintaining a sharp mower blade. A sharp mower blade will cut the grass blade cleanly. This gives the lawn an even appearance and reduces disease from damage caused by a dull mower blade. Mow in the direction that is safest. Periodically change directions if desired, although mowing the same direction each time should not be a problem on taller turf typical of home lawns. The first and last mowing of the year can be slightly shorter, but not so short that you scalp the lawn. Scalping in spring and allowing the grass to remain excessively high at the end of fall encourages weed and disease problems.
If you have other questions about your garden or landscape, feel free to contact a master gardener at the University of Illinois Extension office in Charleston at 217-345-7034. You can also check out the many horticulture webpages at the U of I Extension’s website by visiting http://web.extension.illinois.edu/ccdms/. And be sure to like the Master Gardeners’ new Facebook page, at www.facebook.com/ColesCountyMasterGardeners.