To Mulch or Not to Mulch: Grass Clippings on Clay Soil

Leaving grass clippings on the lawn (mulching) returns nutrients and organic matter—but only if done correctly. On clay soil in hot, dry climates, clumps of unmulched clippings can smother and kill the grass beneath within days.

True Mulching Requires a Mulching Mower

A dedicated mulching mower chops clippings into fine particles that filter down between grass blades to the soil surface, where they decompose quickly. Simply discharging clippings from a side-chute mower without a bag is not mulching—it leaves mats that block sunlight and kill grass.

Prevent Clumping

• Mow frequently enough that you never remove more than one-third of the blade height.
• If clumps form, rake them to distribute evenly or run over them again with the mower.
• Consider a mulching kit or dedicated mulching mower if your current mower doesn't finely chop clippings.

Proper mulching builds soil health on clay; improper clipping management destroys grass. The difference is in the particle size and distribution.