Denver winter gardening: Maintaining compost piles

Compost is a must for organic Denver gardeners. Even if you use Hugelkultur piles, you'll also need compost to amend soil in other beds. Denver winters can be harsh, however, they are generally milder than in the rest of Colorado. That makes it easier to maintain compost piles. That being said, it does still snow and get well below freezing in the metro area, for at least a couple months in winter. So, how do you tend compost in mile high snow and freezing temperatures?

Sometimes tending compost is just impossible.

You're not going to be able to tend your compost piles in 2-3 foot snow drifts. That's OK. The snow will provide needed moisture for the pile. You won't always be able to effectively till frozen compost either. That's OK too. Provided, that is, that you have been diligently tilling up to that point and continue to do so whenever possible.

Denver warm spells

Denver warm spells are of great benefit when it comes to maintaining compost piles in winter. Be sure to take advantage of them. Whenever the pile is warm enough to till, be sure to get out there and get it done. If it seems dry, add water. This is important because in drought years, compost piles will not get enough snow to keep them cooking.

How about that Denver sun?

Use it well in winter. Placing a cold frame over compost piles in Denver can effectively keep compost hot nearly all winter. That means composted soil will be ready to use much sooner. This doesn't always work in colder climates, further from the sun, like in the eastern U.S. However, for Denver, with those 300+ days of sunshine and mile high altitude, it's a perfect solution.

Note: If you don't have a cold frame or glass, use clear plastic to warm compost with the sun.

Don't forget to make additions.

Throughout the winter months, be sure to add kitchen vegetable waste, coffee grounds, etc. to your compost pile, just as diligently as you would in warmer months. Keep a bucket in the kitchen to collect scraps on snow days. These can be brought out weekly, on good weather days. Denver snow doesn't generally “stick” or accumulate for more than a few days due to the close proximity of the sun.

Tip: Hot, black, leftover coffee (straight from the pot, with nothing added) provides both warm moisture and nutrients to the compost pile in winter.

Straw cover:

Straw makes excellent insulation for compost piles in winter. Covering your compost and Hugelkultur piles with straw insulates them from the cold so they can cook all winter. You will have to remove the insulating straw from compost piles to turn them. Still, it's well worth the effort in order to have your compost done by spring.

Note: To add kitchen scraps in the cold, simply make a hole in the straw, then re-cover. Till the scraps in on warmer days.