What you need to know about winter composting

Learn how to keep your compost pile hot when the weather is below freezing.

Just because the weather is cold or outright icy and snowy doesn’t mean your outdoor compost pile has to hibernate for the winter. After all, there are still kitchen scraps, leaves, and other materials to deal with. Even in cold weather, composting outdoors during the winter is relatively simple. Compost piles aren’t very productive, but that’s okay. I won’t be doing any gardening during those months anyway.

The arrival of spring will give you a head start on compost production for the rest of the year. The following steps will help you continue composting outdoors throughout the winter.

How much you engage in composting in the winter will depend on how ambitious you are, but in most cases, you won’t need to do much. The smaller the compost pile, the more likely it is that the process will not slow down at all or even stop in the coldest months.

The main goal is to keep the center of the compost pile or bin hot enough to activate the bacteria inside. The best way to do this is to simply add the ingredients and let nature take its course. Most experts do not recommend turning over piles much during the winter.

Cut or shred any additives, especially brown material, that will help the compost build up over the winter. The smaller the pieces, the faster they will break down.

The basics of composting

Compost piles and bins vary greatly in size and complexity. It all depends on personal preference and how much material you produce for composting. One person with a small yard can make much less compost than a family of four or more with an acre of land. If the process seems overwhelming, start small.

The general guidelines for composting are the same whether it is summer or winter. You want to add a mixture of “green” ingredients that provide nitrogen. This includes kitchen scraps, coffee grounds, plant trimmings, etc. You can also add pesticide-free, preferably herbicide-free, green lawn mowing. Spread the latter out so they don’t stick together and rob you of much-needed oxygen.

It is also a good idea to include a ‘brown’ material that adds carbon. Good choices include cardboard, newspaper, brown paper, leaves, dry grass clippings, brown thatch, sawdust, and wood shavings.

Add twice as much brown stuff as you would add to the pile. For best results, layer the brown material on the bottom and top of the pile. Lastly, add some water. Grey water from the kitchen or shower works well. This will keep the pile moist. Depending on how dedicated you are, replace them every few days or every two weeks from spring through fall. Give it a little spin in the winter. You don’t want to disturb the warm center too much, and with a lot of snow it’s too much work.

Learn more about composting

Fallen leaves can be good food for your winter compost pile, but too many can upset the overall balance. Maintain an ideal ratio of no more than two-thirds of leaves for every one-third of green waste. It’s also best to tear it into small pieces to avoid lumps.

Avoid using evergreen leaves as they decompose much more slowly than leaves of other trees. Other leaves to avoid include black walnut and eucalyptus leaves, which contain natural herbicides. Oak leaves are used sparingly, using only 10-20% of the “brown” material.

If you have a lot of leaves or don’t want to tear them up, consider building a pile of leaves in another corner of your yard. It will break down much more slowly than a standard compost pile, but if you’re willing to wait, you’ll eventually have a great mulch to add to your garden.

Getting started
The easiest way is to continue adding to the pile or bin throughout the winter. There may not be much compost available in early spring, but once the weather changes, things warm up quickly and production begins.

If you store your compost in a simple pile, place it in a sunny area if possible and aim for 1 cubic yard of compost. This will ensure there is enough insulation to keep the center of the pile warm. Adding more material throughout the winter may require digging up the pile or removing snow or ice.

To add a little more winter protection and keep things tidy, you can build a wall around the pile.

There are elaborate systems, but you can also use concrete blocks or straw bales to collect compost. Building against a wall or fence facing south or west also takes advantage of reflected solar heat to keep the compost warm.

Find your compost bin
Hinged roofs serve three purposes: Prevents compost from being used by large animals looking for food. This will help keep your compost warm regardless of the climate. And if you live in a climate that gets a lot of snow, this will help keep rain and snow out of the compost itself.

To keep the pile moist, moisture must be replenished from spring to fall, and even in winter, low humidity or dry winds that bring too much rain or snow can “drown” the microorganisms in the pile. If this happens, adding more “brown” material, such as shredded cardboard, may help absorb moisture.

Another option is to bury compost in your garden. It takes a little more work to set up and maintain because you have to dig and maintain a space for the compost, including keeping the materials in place and discouraging animals. If you choose a place to plant in the spring, such as a vegetable garden, you will already have plenty of materials available for use in the spring.

One way to do this is to spread rows of compost over your vegetable garden rows after you’ve harvested everything you need for the season. It is advisable to dig the soil a little deeper to provide insulation for the material. Then fill it with kitchen scraps and other compostable materials.

Another neat option is to cut off the bottom of a plastic trash can and bury it in the dirt. This creates insulation that keeps things warm. Typically, you may need several, depending on the amount of green waste you generate.

You can also add a roof or tarp over the pile to keep it neater.

Then, when spring comes, enjoy the comfort of your winter landscape, knowing that you’ll be one of the first to receive free homemade fertilizer for a beautiful, productive garden.