Often taken for granted as just a routine task done all season, mowing has an enormous impact on lawn appearance and health. Sound mowing not only enhances lawns visually but reduces common problems, especially weeds. Lawn mowing is still weeks away but now is an opportune time to review sound mowing guidelines.
First things first. Was your mower properly winterized at the end of the season last fall? How well was the machine running last season? When is the last time the blade was sharpened or replaced? Now is the time to address mower maintenance to ensure it is ready to go when needed later this spring.
Improper mowing height is the easiest correctable lawn care mistake that pays huge dividends. Lawns mowed too short face a variety of issues, in particular weed infestations. Grasses found in Wisconsin lawns, including Kentucky bluegrass, perennial ryegrass, and fine fescues suffer when mowed too close. An ideal mowing height is around three inches. Lawns do not need to be cut shorter the first mowing of spring.
Lawn grasses mowed at proper heights develop deeper roots and hold up better as conditions get warmer and drier when summer arrives. Crabgrass, a huge weed problem across Wisconsin last summer, flourishes in open stands of turf that allow more light to hit the soil. Taller grass resulting from higher heights of cut shades the soil, resulting in much less crabgrass. If nothing else is changed except raising an excessively short height of cut, a dramatic improvement in lawn quality will be noted.
Proper mowing frequency is the second key mowing guideline. Mow based on the rate of grass growth, not the weekly calendar, and follow the rule of one-third, removing a maximum of one-third of the grass leaf. Often this means mowing more than once a week in cool, wet spring weather. Conversely, mowing intervals may lengthen to only every 2 weeks or longer during drier summer weather.
Follow the rule of one-third and there is no need to collect clippings, as they will readily filter back down into the lawn and decompose. Clippings returned do not cause thatch issues. A major benefit is clippings recycle nutrients, in particular nitrogen. This translates to applying less nitrogen fertilizer to lawns over the course of the season, as compared to removing clippings.
As mentioned earlier, sharpening mower blades should be part of the preseason equipment maintenance. Check and sharpen again during the season as needed. Dull blades will shred grass leaves, resulting in a whitish cast to lawns after mowing. Periodically changing the mowing pattern direction can also help mowing quality.
Bruce Spangenberg is a Horticulture Outreach Specialist with UW-Madison Division of Extension. Get answers to your lawn, landscape, and garden questions anytime at www.go.wisc.edu/GardenQuestions
By Bruce Spangenberg, Horticulture Outreach Specialist, UW-Madison Division of Extension
