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Why you should be lazy and leave your leaves in the yard

Fallen leaves can provide critical wildlife habitat and benefit soil health

October 14, 2023 at 7:00 a.m. EDT
To best support wildlife and soil health, experts say leaves should be left where they fall. (Matt McClain/The Washington Post)
5 min

As leaves begin to blanket yards across the country this fall, many might be tempted to clear away the crunchy foliage. Not so fast, experts say.

“The fallen leaf layer is actually really important wildlife habitat,” said David Mizejewski, a naturalist with the National Wildlife Federation, a nonprofit conservation organization. “All sorts of creatures rely on that for their survival as a place where they can find food and cover, and in many cases even complete their life cycle.”

But Mizejewski and other experts say you don’t have to let a thick layer of leaves carpet your entire yard to help support the environment.

“Have a little chaos in parts of your garden and that’s really beneficial for the soil and for the animals that need to share these landscapes with us,” said Scott Black, executive director of the Xerces Society, a nonprofit dedicated to invertebrate conservation.

Here’s what you need to know about how to manage fallen leaves this season.

The ‘no mow’ movement could transform our lawns

Leave them

Bagging up your leaves and sending them to a landfill “is by far the worst thing” to do, Mizejewski said. In 2018, landfills received about 10.5 million tons of yard trimmings, which includes leaves, or just over 7 percent of all waste thrown away, according to the Environmental Protection Agency.

“What happens when those things get buried in the landfills is they break down in anaerobic conditions with no oxygen, and that produces methane, which of course, is a potent greenhouse gas,” he said.

To best support wildlife and soil health, experts say leaves should be left where they fall. A hearty leaf cover provides a habitat during the cold winter months for critical pollinating species such as bees, butterflies and moths. Other critters including amphibians and small mammals like chipmunks can also benefit from shelter provided by leaves.

“It allows them to make it through the winter and then emerge to potentially pollinate your garden, to help control other pests,” Black said.

While a light scattering of leaves on a lawn could also be beneficial to your grass, too thick of a layer could smother the turf, experts said. Mizejewski added that the fallen foliage might also harbor pests, such as ticks, so it’s important to follow best practices to protect yourself.

Still, he and other experts said removing all the leaves isn’t the answer.

“You don’t have to keep them on your lawn where they fall, but what we want you to do is keep them on property,” he said. “Don’t get rid of them.”

Move them

If you don’t want leaves all over your yard, experts suggest getting out the rake and moving them into garden beds, piles or to the edges of your property. Try to avoid using gas-powered lawn care equipment, such as leaf blowers, because they produce emissions and can be noisy.

Think about moving the leaves before the first real frost, said Kevin Carpenter-Driscoll, the environmental coordinator for the city of Greenbelt, Md. By the time it starts to get cold, the leaf layer might already be full of wildlife hunkering down for winter and raking the leaves could disturb them, Carpenter-Driscoll said.

Leaves can act as mulch and a springtime weed suppressant. Mizejewski recommends not removing leaves from the base of trees and shrubs.

“They fall right around the root zone of the plant where they do things like suppress weeds, retain soil moisture, and then they slowly break down and compost and return their nutrients right to the roots of the plant,” he said. “That sounds an awful lot like mulch and fertilizer.”

In garden beds, Mizejewski suggests arranging leaves to form a layer about three to five inches deep around your plants. If you’re concerned about leaves blowing back out into your yard, try wetting them down a little.

If you have too many leaves, one option is to use a mulching mower to chop them up, which can help them decompose faster. But avoid mowing all the leaves and eliminating the shelter for wildlife, experts said.

Compost them

Leaves are beneficial additions to compost piles, Mizejewski said. You can make a big leaf pile somewhere on your property that will naturally compost down into leaf mold. Mowing leaves smaller can also help them compost faster.

Additionally, some municipalities will collect leaves for composting. In 2018, an estimated 22.3 million tons of yard trimmings were composted or wood waste was mulched with a 63 percent composting rate, according to an EPA analysis.

Experts said taking steps to leave leaves around your yard in the fall is just one part of a larger effort to move away from manicured lawns that are dead zones for many species, providing little to no habitat or nutrients for wildlife and requiring many resources, including fertilizer, to maintain.

“Ideally, I would love to have this cultural change effect where people are starting to kind of reassess how they view and interact with their own environment and their yards,” Carpenter-Driscoll said. Organizations such as the National Wildlife Federation and the Xerces Society have launched public education campaigns to encourage people to shift toward more natural yards with native plants. This year the National Wildlife Federation designated October as “National Leave the Leaves Month.”

A simple change like not getting rid of all your leaves can have a noticeable impact, Carpenter-Driscoll said.

“You will see a wider variety of species in your yard,” he said. “Take time to go, ‘Okay, what am I seeing that I wasn’t seeing before? How is the soil different than it was before?’ There are tangible changes.”