If you are wondering what to do with your piles of leaves covering your lawn in the fall, it turns out that mulching them and returning them to the lawn offers many benefits. If there is an abundance, you should use them as mulch for gardens and planting beds or as a filler for your compost pile. Don't waste them by putting them on the curb, especially if they will just end up in the landfill. Leaves are free organic matter and should be used on the property they came from when possible.
How to Mulch Leaves
Just like grass clippings, leaves should be mulched with a mulching mower. A mulching mower uses unique mowing blades in conjunction with "baffling" under the deck. The leaves or grass clippings are cut multiple times as they circulate in the interior chamber. The finely chopped material eventually gets pushed down onto the lawn surface. Occasionally, leaves will have to be mowed several times. It may seem a little tedious, but it is far more cost-effective and labor-saving than alternatives like raking or leaf blowing.
A study by Michigan State University indicates that mulching is 100 percent beneficial for the lawn. Mulched leaves are decomposed by earthworms and microorganisms and turned into plant-usable organic matter. Mulched leaves are better for the greater community, too, because they stay on-site and out of landfills.
In the study, many types of leaves—including oak and maple leaves—were mulched and redistributed through test lawns and found to have either a negligible or beneficial effect on turf quality and color. They had no negative effects. Mulched sugar maple leaves even appeared to inhibit broadleaf weeds such as dandelions.
Oak leaves seem to be surrounded by myth and misinformation when it comes to their role in mulch. While it is true that they seem to take forever to fall from the tree, and the leaves themselves are rigid and tough to mulch, the mulched oak leaf is not acidic. The Michigan State study indicates that there was no change in soil pH after six seasons of mulching oak leaves into a lawn.
Lawn Care Maintenance
Many people who share negative views on mulching leaves in the fall have stories about their lawns being smothered or grass becoming weak and thin. It is true that matted layers of unmulched leaves have negative effects.
To prevent this, do not mulch to the point where the leaves cover and smother the grass. The grass blades should be vertical and visible through the layer of mulched leaves. In certain areas, it may help to spread the mulch around from thick spots to areas with thinner mulch distribution.
If mulching is done correctly and lawn performance is still poor, there may be another factor: Soil microbial life may be lacking. Mulched leaves are an amendment to the soil, not a replacement for fertilizer. Fertility still needs to be maintained with fertilizer applications. The microbes in healthy soil assist in the breakdown process and to avoid a matted layer of mulch.