Steam emanating from your compost in the dead of winter is a good thing, it means your pile is 'cooking' and actively breaking down into the rich fertile compost you'll need come spring. Compost may be easily made, nature does most of the work, but it needs a little TLC over the cold winter months. A well maintained compost pile will ensure you have enough available for seed starting, and to amend into the soil once spring comes around again.
1. Feeding You Compost Pile In The Winter
To keep the compost pile cooking as it should all winter, you need to feed it a healthy balance of green and brown items.
Brown items suitable for a compost pile are high carbon organic waste such as dried leaves, straw, hay, wood chips from untreated wood and even shredded newspaper.
Green items are compostable things that are high in nitrogen such as kitchen scraps, fruit, coffee grounds, tea bags, and if you cut your own hair even human hair can be added. Items such as eggshells are fine too, they add calcium, but don't really help the cooking process much.
2. Particle Size
Smaller particles compost faster than large ones. If you can blend up kitchen scraps, or even chop them up before tossing them in the pile that would be just swell. Large items such as discarded fruits and vegetables won't break down fully by spring. The finer the particles the better. Small items are best. Brown items such as shredded newspaper and leaves will compost much faster if shredded before adding them to the pile.
3. Keep The Compost Moist
You want your compost pile to be moist, not saturated and soggy. The moisture is needed for the microbial activity. A dry compost pile is a dead one. Adding a little hot water from time to time wouldn't hurt. I'll go out and dump a tea kettle of boiled water on mine every now and then.
Compost piles that are in a bin or covered wont get any natural water from snow and rain so it is essential that you add some periodically.
4. Layer Your Compost Pile
Layering is a good idea, but not a mandate. The compost pile will do better if you layer the green and brown items.
Layering your pile will help to ensure that the micro organisms working to break down your pile are well fed and kept active by being fed a balanced diet. Layering also traps gases that generate heat within the pile.
A good way to keep your compost pile going in the winter is to keep it insulated. It not only keeps the pile warm but holds in moisture. Other ways to insulate the compost are with layers of dry leaves or straw.
Come spring when you are ready to use the compost it is good to sift it. Sifting will divide the usable compost from rocks, sticks, twigs, rocks and clumps of non-decomposed organic matter. Sifting also further aerates the compost, encouraging further decomposition for a healthy soil structure.