Clumps of grass clippings on the lawn are not only unsightly — they could hurt or even kill the yard grass. Whenever your push mower leaves clumps of grass clippings on the lawn as you mow, the likely causes are wet grass or permitting the grass to get too tall before you mow. You can’t control the weather, but it is possible to maintain a healthy, clump-free lawn by making some changes in how you mow the yard. Suggested turfgrasses for light, Mediterranean climates include Bermuda (Cynodon dactylon, U.S. Department of Agriculture plant hardiness zones 7 through 10), and Zoysia (Zoysia japonica, USDA zones 5 through 10).
Mowing when the grass is wet doesn’t hurt the grass, however, the clumps left on the yard are unsightly and can cause problems when they are not eliminated. Mowing when the grass is too tall is far more likely to hurt the yard than mowing when it’s wet, so you may realize you have to mow wet grass from time to time. On these events, remove the clumps instantly.
To stop clumps from long clippings, never remove more than one-third of the length of the blades of grass at one time. For example, to maintain a lawn at a height of 2 inches, let the grass grow until the blades are 3 inches tall before you mow. In case you have to allow it to grow taller than standard because of rain, then remove one-third of the length of the grass twice a week or so until you get to the desired height.
Effects of Grass Clumps
Leaving grass clippings on the lawn after mowing can provide as much as 25 percent of the annual fertilizer needs, so it is best to leave them on the yard unless they’re clumped. Clumps of clippings block sunlight and cause yellow leaves. Eliminate clumps of clippings by raking or mowing over them in a day or 2 when they’re dry. If you make a habit of leaving clumped clippings on the lawn, the grass may finally die.
Push Mower Blades
Mulching blades chop the pliers to finer pieces than standard push mower blades. Finer clippings are not as likely to clump, and they break down quicker than more than clippings. Dull blades tear the grass rather than cutting it and also give the grass a brownish cast, so keep the blades sharp. Torn bud also encourages disease and increases fuel intake when you mow.