The hidden life beneath the leaves

As temperatures drop, frogs, toads and many other small creatures seek refuge underneath the fallen leaves. “If we took the roof off our house, we’d be really cold in winter”, says Matthew Shepherd, who works at the Xerces Society for Invertebrate Conservation. If we leave the leaves, we’re leaving a warm winter home for cute – and less cute – creatures.

Hedgehogs once thrived across Europe, but urban expansion is pushing them towards extinction. Piles of leaves are their perfect homes. Raking or burning leaf piles can harm or even kill them. So, if you love hedgehogs (and we all do, right?), leave the leaves and even consider adding a hedgehog house to a sheltered place in your garden.

For every square meter of yard with leaves left untouched, “there’s on average almost 2,000 insects that will emerge over the course of the spring”, entomologist Max Ferlauto says, who compared the ground life of soil with and without autumn leaves. Among those are 300 wasps (important pollinators), 400 beetles, and about 20 moths and butterflies. In fact, 90 percent of all moth species spend winter in cocoons underneath the leaves. All these tiny tenants perform essential ecological services, from pollinating to pest-control.

Not a fan of the idea of 2,000 insects crawling out of every square meter of your garden, then maybe you like the idea of them being eaten by birds. Non-migrating birds feast on sheltering bugs, while migratory birds returning in spring feast on the insects that survived the winter in your leaf-covered garden. So, less raking, means more birds.

As insects and worms munch on what looks like waste, they turn it into new, nutrient-rich soil. These creatures are essentially tiny compost machines. Yards that are raked year-after-year have 24 percent less carbon in soils, than yards that are left unraked. This carbon is key to plants’ nutrition and the soil’s moisture-holding capacity, The New York Times writes.

Leaves are great natural mulch for flower beds. As they slowly decompose, they feed nitrogen into your soil and increase the moisture retention capacity of the soil, which makes for thriving spring gardens. Way more sustainable and cheaper than buying bags of bark chips.

In some countries, raked leaves still end up in landfills. In the United States, discarded leaves make up 12 percent of all yearly municipal solid waste. A lot. The leaves that rot in landfills release methane, a greenhouse gas that contributes around 25 times more to global warming per kilogram released than CO₂. Leaves left to decompose in the open air don’t release methane.

If you must rake your leaves or really hate the look of a garden full of leaves, then move them to a place in your garden where they can still do their magic. Preferably to a mowed part of your garden or otherwise maintained area, that are normally not so biodiverse. You’re now creating a shelter that otherwise wouldn’t have existed.

Another option is to wait until they’re crunchy, then mow them into little pieces and leave them. They will serve as mulch and will protect your soil.

You can also compost your leaves. But be sure to manage your compost heap well, in order to prevent anaerobic digestion, creating methane.

Whatever you do, please don’t put them in trash bags or in your organic waste bin to be sent to the landfill. Sometimes, the most helpful thing you can do for nature is absolutely nothing. How wonderful.