Prevents Soil Erosion
A bare patch of soil is begging to wash away during heavy rains, but a thin layer of grass mulch acts like a natural mulch blanket. Originating from turf grasses like perennial rye (native to Europe) and Bermuda grass (native to Africa), those clippings quickly form a protective carpet that cushions raindrops and holds topsoil in place.
Even on slopes, grass mulch slows runoff, giving water time to seep in rather than carve gullies. I once rescued a sloping flower bed from muddy chaos by leaving my clippings in place—no more washed-out petals or exposed roots!