Starting Compost in Winter – Here’s What You Need to Know

Composting boosts soil quality, reduces landfill waste, and provides many other benefits to your garden and the larger environment. While most people think of composting as an activity for the spring and summer, winter composting is also useful – and growing in popularity among gardeners.

Here’s a closer look at starting compost in winter, including why it’s useful, potential problems to watch for, and everything else you need to know to succeed. 

Why You Should Start Compost in Winter

Starting to compost in winter has many benefits. First, it’s good for the environment because it reduces carbon emissions and landfill waste. By composting in the winter, you can make more of a positive environmental impact than if you only compost in the warmer months.

Additionally, composting adds important nutrients to the soil. It reduces the need for harmful fertilizers and pesticides, resulting in safer food. By composting during the winter, you help ensure your soil is ready as soon as the weather warms.

Adding compost to soil also helps plants grow more quickly. Maximizing the growing rate of your garden is often more important in climates with cold winters because the duration of the growing season might be relatively short.

How to Start Compost in Winter

While many of the basic elements of composting remain unchanged regardless of the season, winter composting does require a few adjustments.

First, your winter compost pile should be fairly large, at least one cubic yard. A large compost heap stays better insulated against the cold. The interior will stay warm when the pile is adequately insulated, allowing the composting process to work. If you live somewhere with cold, windy winders, you’ll want to surround your compost tumbler or bin with leaves or hay bales to provide additional insulation.

Winter composting requires two types of organic material: the green group and the brown group. Greens include kitchen scraps such as vegetable peels, fruit, coffee grounds, and cores, while the brown group includes leaves, twigs, grass clippings, and shredded paper. You’ll need to place the two groups in alternating layers, starting and ending with brown.

During the winter months, you’ll want to turn the compost less frequently than you would in the summer. Mixing too often ends up dropping the temperature inside the compost bin (or worm bin). You want the temperature of the compost to stay warm so that the material can decompose.    

Finally, when using a bin, you’ll want to keep it full to help retain heat as efficiently as possible. A large compost bin with only a tiny amount of material won’t decompose correctly because the mass of cold air in the container’s space will slow the biological processes. 

FAQ

Here are answers to common questions about composting in the winter.

How Do You Activate Compost in Winter?

Build your compost pile with layers of browns and greens. You want a 3:1 ratio of dry to wet material, with a brown layer on top. If the compost material smells, it’s likely too wet, so you’ll want to add dry material such as leaves and bark. However, if it’s too dry, it won’t decompose, so you’ll need to add fruit rinds and other organic material.

To start the composting process, you can add a compost activator, which is a collection of microorganisms and nutrients that begin decomposition. While it’s practical, it’s usually not necessary, as the decomposition process will start on its own as long as the temperature and moisture levels are appropriately set. You can also use the Bokashi composting process, which uses fermented organic material.

Another way to start the process is by adding finished compost to your pile, such as compost from the previous season. You don’t need much. Even a tiny amount of active compost is enough to begin decomposition (it works similar to the process of growing yeast).  

How Can I Speed Up My Compost in the Winter?

While composting during the winter isn’t as efficient of a process as its summer counterpart, you can increase the speed somewhat. The best way to do so is by cutting materials in the brown group into small pieces. Smaller scraps decompose at a faster rate.

Aeration also increases compost speed. You want oxygen to gently flow through the compost at all times. However, keep in mind that it can slow down the decomposition process if the air is too cold. Maintaining sufficient insulation is a critical element of adequate aeration.  

How Often Should You Turn Compost in Winter?

You’ll want to turn your compost less frequently in winter than summer. Turning it disrupts the heat stored inside the pile, which slows down the decomposition process.

The exact turning schedule to follow depends on a few factors, such as the humidity and temperature levels, so you might need to experiment somewhat. With a compost in the summer, you might turn it every three or four days.

However, with winter composting, you can turn it about once a week, or even less. Some gardeners only turn the compost monthly, although that’s not recommended unless your bin is extremely well aerated.

Should I Cover Compost in Winter?

Yes, a cover is necessary for winter composting. A tarp is a popular, effective, and versatile solution.

• A cover such as a tarp traps heat into the pile. Decomposition only occurs if the temperature in the pile is warmer than the outside air.
• A tarp also acts as a barrier against rain and snow, as excess water can ruin your compost.
• A cover also protects your compost from animals and insects, which are naturally attracted to the smell of food scraps.

Even if your composting bin already has a cover, adding a tarp is often recommended as a second layer of protection.

Final Thoughts

Starting compost in winter has more benefits than many gardeners realize. It not only adds nutrients to your soil but it allows you to maximize the efficiency of the growing season. The key to winter composting success is protecting your pile from cold temperatures and water. Also, don’t turn it too often, but do keep it well aerated.

Taking the time to compost during the winter months can substantially improve the quality of your garden during the growing season.