Composting when it's cold out

Baby, it’s cold out.

As the temperatures drop, you’ll notice that a lot of things are seeming to slow. For example: how fast we get out of bed in the morning, how long we take to make our dinner, our overall social calendars, and, of course, the rate of decay in our compost piles. Cold weather means a more gradual process of rot, and you might start to notice that your compost isn’t “digesting” your food scraps as quickly as it once was. Compost, like a bear, tends to hibernate. Luckily, there’s a few things you can do to keep your pile active for little while longer in winter—and, when it comes time, retire it comfortably for the winter, to be reawakened in the spring.

**Editor’s note: I spent two hours trying to make an app generate an AI image of a bear sleeping in compost, but I’m not convincd that AI knows what compost is.

Harvest first

Remove and use (or give to friends) any compost that’s “finished” in your pile. This will help you make room for new additions, throughout the winter, that are likely to decay more slowly.

Keep your compost cozy

You can keep your compost more active, for longer into the winter, with a little insulation. Surround your pile with a thick layer of material, like straw or grass clippings. It will need to be about a foot thick in order to be effective. You can also strap a black tarp over everything, which does double duty for you: it keeps the heat in, and it keeps the winter elements (rain, ice, snow) solidly out. Any color tarp will technically work, but you’ll do best with black due to the heat-absorbing capacity of the color. If your pile is in a bin versus open air, this will require some extra work. Take your compost out, line your bin with insulating materials, and pile everything back in again.

Get some sun

If possible, you should also think about relocating your pile into direct sunlight. Every second of sun—and thus, heat)—that your heap can absorb will help it stay active for longer.

Be mindful of your materials

In summer, I can get a little lazy and you are likely to find whole broccoli stalks and full branches in my compost. Not in winter, though. When things get cold, and the decomposers in my pile start to get a little sluggish, I like to give them a leg up on breaking things down. That means I’m much more methodical about chopping everything into tiny little bits (sounds murderous, sorry) before I toss it in.

Keep your ratios right

There’s a few ways to do this. Whenever I add greens (food scraps, grass), I make sure to add a layer of browns (cardboard, wood chips, dead leaves). If you’re lacking for brown material in winter, though, you can always add it in bulk after the first thaw in spring. Just make sure to thoroughly turn and mix the pile, once you do. You can also dig a hole straight through the center of the pile and leave it, making sure to drop your food scraps directly into that hole whenever they’re added. That way, you’re easily integrating new additions throughout the pile versus just leaving them in a big clump on top.

Be ready to troubleshoot

Winter weather can be unpredictable. Your goal is to keep your pile warm enough, aerated throughout, and not too wet. If it’s going to snow or rain, you might want to bundle things up extra tight. If your pile is under a tarp throughout a dry winter, though, you might want to open it up and make sure to wet it down occasionally. You might also think about lifting your compost onto a platform, so that it’s not absorbing groundwater or snowmelt.

Let it go

In the depths of hard, frozen winter, it’s okay to forget about your compost. You can cover it, leave it, and return to it in the spring. It will come back alive with a good turn or two, and by adding some fresh food scraps. How many other things in life can you say that about? Embrace it

PS. As a reminder, anybody this month who upgrades to a paid subscription will get a free “I Love Rotting & Decaying” sticker.