Raking Leaves This Fall? Here's Why You Should Actually Keep Them
While some of us mourn the end of summer, there's so much to love about autumn. Cozy sweaters, hot cider, and of course, the brilliantly colored fall foliage in our landscapes. But fall is also tied to an annual event (or garden chore, depending on how you view it) that follows the pretty leaves we all enjoy. Throughout the temperate United States, millions of trees and other plants prepare for winter by shedding their foliage and going dormant. This is a wonderful thing when it happens in forests and other natural areas, yet when our lawns and gardens get blanketed by all those leaves, we feel compelled to clean them up. Before you break out your rake or leaf blower, however, you might want to consider your alternatives.
Usually, when you collect and bag the leaves in your yard, they end up in the dump. According to the Environmental Protection Agency, leaves and other yard debris account for 34.7 million tons of waste per year in the U.S., about 13.3% of all solid waste in the country. The EPA also notes that yard waste itself generates methane gas, which pollutes the air we breathe, and acids that can leach into the ground, polluting soil and water. Burning your leaves isn’t a great solution, either: The EPA notes that burning leaves contributes to air pollution, can be dangerous for those with lung conditions, and creates a risk of uncontrolled fires. (Most cities and many states have banned burning leaves.)
In addition to these pollution issues and health concerns from disposing of fall leaves, there are the methods used to collect those leaves in the first place. According to David Ellis, director of communications at the American Horticultural Society, "What’s important for people to think about is avoiding the wholesale removal of leaves from gardens, especially if done with leaf blowers." He points out that blowers often blast away the top layer of soil as well, along with habitat for many beneficial garden creatures.
Instead, we should take a closer look at how nature wants to work. "Fallen leaves have value for both natural ecosystems and gardens for several reasons," Ellis says. "In forests (and in woodland gardens), they accumulate on the ground underneath trees, forming a natural mulch that helps suppress weeds and protect roots from temperature extremes." Leaf litter also provides shelter for animals ranging from butterfly larvae to frogs and salamanders. And it’s food for the billions of microorganisms that break it down into the nutrients that plants need. The idea is to stop seeing leaves as garbage that trees throw at you every year, and to start seeing those fallen leaves as a generous gift from our tall, slow-growing friends. Delivery is even free!
That’s not to say that you can necessarily sit back and do nothing. "Large quantities of leaves left on lawns over a long period may damage turf grass," Ellis says. "This is especially problematic if the leaves are large, flat ones found on trees such as sycamores and some oaks, which can form a nearly impermeable mat." If you have huge quantities of big leaves falling on delicate plants in a garden or smothering grass in a lawn, you definitely don't want to leave those leaves where they are. Plus, those big leaves aren’t likely to decompose over the winter unless you intervene.
Ellis recommends using your mower to cut leaves into smaller pieces, which won't mat down as much, will break down faster, and won't take up as much space as whole leaves. Most gas or electric lawn mowers have mulching options that allow you to shred fallen leaves (and grass) into small pieces that can remain on the lawn instead of being collected and bagged for disposal. It's okay to leave them right where they are because they'll continue to break down and feed the grass.
If you prefer a tidier look, you could use a dedicated leaf shredder ($169, The Home Depot). Throw the leaves you collect into this machine, and out will come valuable mulch, which you can use in all sorts of ways in your garden. For example, shredded leaves make the perfect mulch to use in perennial beds before winter comes; layer them about four inches thick but do not cover up the crowns of your plants.
You can also use the leaf mulch around roses to help insulate them during the colder months. Some gardeners like to till shredded leaves into their vegetable plots at the end of the season to help replenish the soil. Or if you'd like to speed up decomposition, put shredded leaves in your compost bin and you'll have rich compost to use around your garden next year.
So go ahead and rake up a big pile to jump in (you know you want to). But you don't need to go overboard with trying to clean up every leaf in your yard. "Restrain the urge for excessive tidiness and find ways to use the natural bounty of leaves that autumn provides," Ellis says. Your garden and the planet will thank you.