Keep up with the mowing ... and the weed growth

I am hearing a lot of people talk about mowing lawns frequently now. And most of the comments are complaining about having to mow every three days because of the rain. I am not complaining about the lawn, but rather about the rate of weed growth.

It will soon be summer, and mowing will slow down, and the complaining will be about the heat, right? Not me, I love the heat and summer isn’t long enough for me; it’s my favorite time of the year.

Have you ever wondered why lawn care companies or do-it-yourself lawn care kits come with four to six applications per year? Some may think it’s for the companies to make more money, but this isn’t the case.

Turf requires around three to four and a half pounds of nitrogen per 1,000 square feet each year. Nitrogen leaches through the soil and doesn’t stick around. Therefore, the total amount of nitrogen is split into four to six applications to provide a continual source of nitrogen.

This recommendation is for those who desire a weed-free lawn. Thick turfgrass prevents weeds from becoming a problem. Weeds will take advantage of thin spots in the turf.

For those who aren’t concerned about a weed-free lawn, don’t fertilize, or fertilize periodically to keep the turfgrass healthy.

Keep your mower blades sharp. Dull mower blades result in the grass blade being cut unevenly, resulting in a brown edge. If you look at the overall lawn, you will see a brownish appearance.

Take a close look at the blade of turfgrass. If the edges are smooth and even, with little to no browning you are in good shape. If they are ragged and brown on the tips, sharpen the blades.

When mowing, remove no more than one-third of the grass blade at a time. This is where the mowing three times a week comes in. Continual removal of more than one-third results in a stressed plant that won’t tolerate drought as well.

Experts also say that it’s better to mow the grass when wet over removing more than one-third of the leaf blade.

Kentucky bluegrass lawns look a little raggedy right now. This is the time of the year when they produce flowers and seed heads. After a couple of mowings, this will clear up.

If you want to use weed control, mid to late May is a good time to work on the broadleaf weeds. If you can wait until September, it is even better. Many like to spot-treat noticeable weeds now and then hit the majority in September.

Late summer (September) is when the weeds are actively storing sugars and take the herbicide into the root system more efficiently.

Finally, if you seeded a new lawn or spots in the lawn last fall or this spring, wait until you have cut the grass at least four times before applying any types of herbicide.

Happy mowing!

Pamela Corle-Bennett is the state master gardener volunteer coordinator and horticulture educator for Ohio State University Extension. Contact her by email at bennett.27@osu.edu.

Proper mowing and fertilization reduce the need for herbicides.  The front of the research plot in this photo has numerous broadleaf weeds while the back has very few.  The front was not fertilized and mowed short and the back was fertilized properly and mowed at the proper height.

Credit: Contributed

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Credit: Contributed

Ragged edges of a turfgrass blade indicate that mower blades need to be sharpened and mower speed should be slower.

Credit: Contributed

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Credit: Contributed

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