Bag the Rake, Not the Leaves
Each fall, as the trees change color across the northern half of the United States, homeowners begrudgingly come out of the houses on those precious few weekends before winter arrives to do a wasteful thing: rake. For starters, it causes blisters on the hands and frustration in the mind, but it also consumes an enormous amount of time. Depending on the tree cover in and the size of your yard several days could be spent with this task. The only positive spin I can put on raking is the exercise it creates for the upper body and the heart but this benefit can be had without the toll on your yard raking takes.
The trees get a boat load of carbon each year from the atmosphere through photosynthesis by turning carbon dioxide into oxygen as a part of all plants’ respiration. But that’s only part of the equation. In addition to carbon, plants use their roots to mine the dirt for nitrogen and other minerals required for their structure. By raking these leaves at the end of the growing season and sending them off-site to be composted breaks the natural cycle of soil replenishment that occurs. The last thing you want to do with leaves though is throw them in the trash — if your trash goes to a sanitary landfill, you’re actually contributing to the creation of methane as the leaves will likely decompose anaerobically underground. Bad news.
Ideally, you let the leaves sit in your yard where they will protect the plants during the winter and will slowly decompose and support animal life but that doesn’t sit too well in most suburban developments. And it can also create an environment ripe for the growth of mold because typical yard grasses are too dense to allow solid interaction between fallen leaves and the soil. So, we rake. A few years ago, though, I stumbled upon a better method which I’ll share with you today: mulching. And not in a batch system like a compost bin but by using your lawn mower to shred them right into your grass.
First, if you have a normal sod lawn, short grass during a frozen winter results in a lawn more resistant to freeze damage. Second, mulching the leaves puts the nitrogen the tree borrowed from your soil right back where it came from saving you some of the need to fertilize your lawn with a granular fertilizer which is often packed with chemicals meant to control weeds. Something I wasn’t aware of when I started this fall practice, is that leaves actually contain weed controlling compounds in them meant to control what grows underneath trees. Whoa, bonus! A Michigan State study conducted showed that mulched leaves reduced dandelion growth the following seasons compared to grass plots where no leaves were mulched. The reduction over the first season was 80% with further mulch repetitions in a following year reduced them another 50%.
There are some limitations to this practice. I happen to have two monstrous maple trees in our back yard and the lawn’s ability to digest leaves fast enough in the couple weeks of fall so if your yard is like mine you may have to spread some leaves to other parts of the yard or bag and compost some of them. But for most yards with more moderate tree coverage, 100% of leaves can be mulched with a gas lawn mower and within a few days, the little bits of shredded leaves have disappeared and created a richer soil that will be less weedy in spring. And this benefit doesn’t cause any increase in thatch.
So, leave that rake in the garage, raise the lawnmower up a bit and just run the crunchy leaves over every day or two and give that lawn the breakfast of champions. Sure, you’re burning some gas but suburban life is about a balance of time and money. And look at it this way, if you’re required or just want to keep a tidy, weed-free, green lawn the chemicals needed to do so without mulching leaves have an environmental toll.
For more details on the benefits of mulching leaves, check out this publication: