Why Are Brown Spots in My Lawn: Bad Mowing Practices

There are a lot of things that can cause brown spots in your lawn, which makes it hard to get rid of the unsightly splotches. One cause that’s simple to fix is improper mowing. How you mow your lawn has a bigger impact than you may realize, and there are several specific mowing practices that can put your lawn at risk of brown spots. 

Mowing your lawn too short is a common cause of unhealthy, patchy grass. The rule of thumb is to cut no more than a third of the height of the grass each time you mow. Otherwise, you’ll deprive your lawn of the nutrients it needs. Taking more than a third of the grass height means also taking too many nutrients from the plant. It will have an even harder time replenishing those nutrients since it has less surface area to absorb sunlight and turn into energy. What’s more, the energy the plant puts toward growing back up takes away from growing its roots down. The end result is a weak root system. 

The one-third rule also solves the problem of how often to mow. Rather than following a rigid schedule or measuring rainfall, you can determine the ideal height of your grass type and plan your mowing around that.

Scalping, or cutting your grass down to the stems, creates brown spots immediately because the stems are tannish-brown in color. Scalping also leads to long-term harm because the exposed stems are vulnerable to additional damage from the lawnmower and the sun. 

Dull mower blades damage your lawn by shredding the ends of the grass blades, which is unnecessarily traumatic to the plant. In response to the damage, the grass may turn brown or even die. Be sure to sharpen the blades of your mower at least once a season to ensure a clean cut. 

Another mowing mistake is cutting your lawn when it’s wet. Not only is this practice dangerous for you and your mower, but it can also increase the spread of diseases that flare in wet conditions. Mowing a wet lawn can lead to the spread of weeds, too, because their seeds are more likely to germinate when they’re distributed in moist soil.

If you have brown spots in your lawn that seem to coincide with your mowing routine, that may be the issue. Otherwise, it could be one of a number of other problems causing the brown patches. Check back next week for another blog post addressing a different source of brown spots.