Compost in the Winter

For a terrific spring garden, you should keep your compost pile robust through the winter. After all, planting starts in February! Be prepared with compost that’s been getting ready all winter long.

Here are five specific steps you can take to keep your compost heap in good condition this winter.

1.   Protect the compost from precipitation.

Too much wetness leads to an unhealthy compost heap. You want some moisture, but not five straight days of rain or six inches of snow. Abundant moisture may cause the plant material in your compost heap to rot before it can decompose.

Before winter starts, get a good lid or tarp to cover your compost to protect it from wetness. If you choose to have a tarp, make sure it is sufficiently secure to not blow away in any storms.

2.   Layer greens and browns.

Many composters follow the rule of layering greens and browns. Greens are anything that recently grew or are wet. Grass clippings are green, but not just because they’re literally green: They were recently live blades of grass. Food scraps are green, including coffee grounds — no, they don’t count as brown just because of the color! Greens supply nitrogen, which is an essential nutrient for compost and your garden.

Browns are anything dried or woody. Dry leaves, hay and newspaper are all browns. Browns supply carbon, which is also an essential nutrient. They also provide bulk in a compost pile, so it doesn’t become too compacted and wet.

3.   Watch for pests.

In summer, the green part of compost will happily decompose away. It’s warm, which is optimal decomposition weather. In cold temperatures, it will take longer for your vegetable scraps to decompose.

As a result, your compost pile may attract pests like mice, rats or bugs. If you have small animals nearby, like squirrels or raccoons, it is all too easy for your compost pile to look like dinner if it isn’t decomposing quickly. The solution? Cut back on food scraps in cold weather. Actively turn over your compost to disrupt any animal nests. Use a cover. Spiky greens, like holly, can also discourage foraging animals.

4.   Manage the effects of cold weather.

You need to be vigilant about managing the effect of freezing temperatures on your compost heap. To some degree, a freeze can be good, as the oscillation between very cold and then warmer serves to break down organic material faster. But frozen solid compost is not good, because it becomes a lump of all-too-inert garbage. The microorganisms that break down the compost elements can’t do their job. When you come to plant in February or March, your compost may not be ready.

Veteran composters suggest making your compost pile large, at least one cubic yard. Composting material is warm at the center. The size of a large-enough pile will ensure it doesn’t freeze solid. Packing lots of browns around the pile, like straw or hay, will also serve as insulation.

5.   Let worms help.

There is a reason soil with earthworms tends to be rich. Worms turn the soil and help it breathe. They can do the same for your compost pile. Vermicomposting, as composting using worms is called, is very popular in the winter.

Vermicomposting outside will work in temperatures as low as 40 degrees Fahrenheit. If winters in your area are significantly colder, you will need to bring the compost bin in at night, to a garage or foyer.

Keep composting during the winter to jump-start your garden in early spring. These five steps will help you be a knowledgeable winter composter.