Behlen: Use Your Leaves to Build Up Your Soil

pay to dispose of them somewhere.

I’m sure the landscape guys raked them from someone’s lawn. I’d bet those same guys will spread compost or fertilizer on that same lawn in the spring time. They could have just mowed the leaves and left them on the lawn. They’d break down over time and add to the organic matter in the soil.

Our house lies in the country surrounded by post oaks. When my boys were little, we used to tromp into the woods armed with rakes and a wheelbarrow. We’d cart back piles and piles of dead leaves to spread in the garden. They’re older now and (mostly) moved out, so I no longer have that luxury.

When people bag up their grass clippings and leaves from their lawns, they’re stripping the organic matter from the soil. The soil gets worse and worse over time. They resort to fertilizers. Grassburs start popping up everywhere, because grassburs naturally colonize poor soils. So homeowners start spraying weed killer (or even worse, so-called “weed-and-feed” products) all over their lawn. It’s a neverending cycle.

Compost made from leaves, sometimes called “leaf mold,” provides an excellent source of plant nutrients. Trees mine minerals and nutrients from deep in the soil. Those nutrients end up in the leaves. When they fall to the ground, those nutrients become part of the top layers of the soil. Good compost should smell like the forest floor.

Leaf mold compost literally is the forest floor.

You can make leaf mold compost by simply piling up a bunch of leaves. They break down faster if you mulch them first. This can be easily done by running over piles of leaves with a lawnmower.

You don’t want to mix in any green matter like grass clippings. That would encourage hot bacterial decomposition. Instead, you want natural fungus to decompose the leaves. Fungal spores are all around us in the air and the soil. Just pile up the chopped leaves and let them sit there for a year. You’ll end up with rich, black compost, just like the forest floor.

Or you can use freshly-fallen leaves as a mulch. They’ll eventually break down in the garden soil.

It helps to water them down at first, otherwise the wind will blow the leaves away.

So don’t throw those leaves away. Use them to build your soil instead.