Composting During Winter

Where I live it has already snowed twice, and it won't be long before the soil freezes hard for the rest of the winter. My compost piles will freeze, too, but that doesn't mean I stop composting in winter. Every day of the year, we generate kitchen waste that needs to be transformed into soil-enriching compost.

Dealing With Kitchen Waste in Winter

Sometimes composting has to wait. It can be a long trek out to the composter in ice and snow, and then you get little satisfaction from dumping your bucket of kitchen waste onto a frozen lump of food scraps. To reduce the number of trips to the composter I must make, I like to station a plain old garbage can at the edge of my deck, which serves as a holding place for kitchen waste that needs dumping in frigid weather. The frozen waste doesn't smell, even when mild weather causes it to melt and start rotting a little. In early spring when freezing weather subsides, whatever is in the garbage can gets mixed into the main pile or dumped into the composter.

One of the things I like to do this time of year is to remove some of the material in the composter to make room for more. Most days, the best destiny for kitchen waste is the stationary composter, where it freezes and thaws so many times that the material decomposes quickly when the weather warms. In spring, when I mix the winter food glop with weathered leaves, it rots into a very nice compost indeed sometime in early summer.

Hot Composting Your Winter Waste

I make no attempt to maintain an active, heat-producing compost pile in the middle of winter. To do so would require far more material than I have, because a compost pile needs to be at least 5 feet (1.5 metres) tall and wide to generate and hold heat in winter. I would need to import manure or some other nitrogen source, too, which is not worth the trouble. If I want to heat up a heap to destroy weed seeds or deal with some other problem, I wait until the material is almost done in late spring, mix it with fresh green grass clippings and a little organic fertiliser, and re-process it as a hot heap, which is finished in three weeks when turned every few days.

Some gardeners insulate their compost piles from cold by surrounding them with bales of straw or bags stuffed with leaves, and there are even a few innovators out there who are erecting small greenhouses over their compost to help capture solar warmth – and the other way around! Though I don't have a greenhouse myself, I would love to hear from greenhouse gardeners who have taken their compost under glass in pits and barrels.

By Barbara Pleasant

If your compost didn't work out quite as well as expected this year, watch our video Common Compost Problems & find out how to improve it next year.