Given that some leaves, such as those from red maple trees (Acer rubrum), look quite pretty lying on the grass, you might wonder why it's necessary to break out the rake and get rid of them—after all, it's an awful lot of work. In some cases, raking the leaves may not be necessary—and it might even be better for the environment to leave them. However, in some cases, raking the leaves (or using a leaf blower) may be important for the health of your yard.
When to Rake
Blessed with enough sunlight, nutrients, and water, and enjoying temperatures that are neither too cold nor too hot, cool-season grasses, such as Kentucky bluegrass, revitalize themselves in fall. "Cool-season" lawn grasses are called as such because they are most active during those periods of the year when the weather is moderately cool, such as in the fall. This is when they must "make hay," strengthening their root systems. A thick layer of fallen leaves can get in the way of the growth of these grasses. The leaves can deprive the grass of sunlight if not raked up in time.
If you don't have cool-season grass in your yard, you still may want to rake them. If it looks like the lawn is being smothered or if you think your mower won't be able to handle mulching the leaves, then you can rake the leaves to thin them out.
When the focus is on lawn health, you do not have to rake up every last fallen leaf. The homeowners whom you see hunting down stray leaves as if they were fugitives from justice are motivated by looks; they are striving for the look of a perfectly manicured lawn. If you do not care about that and want to keep your grass healthy, then rest assured that a few leftover leaves can't hurt your lawn. In fact, if you plan on mowing at least one more time that autumn, the mower blade will shred up any remaining leaves.
What to Do With the Leaves
If you rake up your leaves, cut them up and put them in a plant or flower bed or another part of your lawn that doesn't get leaf cover. The leaves will provide mulch and natural fertilizer for parts of the yard that doesn't get it from fallen leaves.
Alternatively, you could put the raked-up leaves in a compost bin. What you don't want to do, however, is put the leaves into plastic bags and send them to the landfill. There, the leave will take up space and the plastic bags will be harmful to the environment. In 2018, the Environmental Protection Agency (EPA) estimated that 12.1 percent of municipal solid waste (MSW) was yard trimmings, which equates to 35.4 million tons.
Reasons Not to Rake
If you're feeling lazy and don't want to rake, take heart that you might be doing the environment a favor. When the leave break down where they fall, they return essential nutrients to the gras and soil. Additionally, the coverage that the leaves provide preserve soil moisture and suppress weeds. Finally, birds and insects such as butterflies and moths depend on the fallen leaves. The pupa take up residence in the leaves during the winter, so raking them up means you won't enjoy the butterflies that come later. Birds also raid the leaf litter to find food for their babies.
Instead of raking the leaves, pass a lawn mower fitted with a blade over the yard to cut them up. Then, simply leave the remnants where they are.