Composting in the winter is possible given you have more patience and winterize your bin. Winterizing is necessary to ensure that compost will reach temperatures of 140 to 160 degrees Fahrenheit in the center of the bin for the decomposition process to work.

Step 1: Changing locations

During the summer, compost bins are placed in shady areas where compost will not overheat. This is not the case in the winter. 

With cold weather, it is important to place the bin in a location where it will receive direct sunlight for as long a period as possible. The sun will help to heat the compost during the coldest days.

Step 2: Insulation

If the compost bin has been open, it needs to be covered. Not only do the sides need insulation to ensure the compostable material remains warm, a lid needs to be placed where the compost is fed.

The bin needs to be insulated both on the inside and the outside. Adding green material such as leaves and straw on the inside of the barrel will help keep the cold from entering the center of the compost. Adding cardboard to the inside of the barrel is another good insulation choice that will easily break down.

On the outside of the bin, there are a few choices for insulation. You can place wood slabs around the bin. They will help to keep the cold temperatures from entering the bin while allowing aeration to occur. 

Hay bales are another low-cost option. Stack the bales up along all sides of the bin. This will keep the warmth inside of the bin. 

Styrofoam is another option.  It will keep the cold out of the bin and heat within. The downfall with Styrofoam is that it won’t let air into the bin as easily as straw or wood.

The compost bin can also be placed in the ground. To do this, dig a hole in the ground big enough to hold the bin and its extra insulation. The ground will conceal the bin from harsh winds and winter elements while holding the bin’s heat.

Once the bin is insulated, cover the insulation with a dark tarp or black plastic. The dark color will attract the sun warming the contents. The covering will also add extra protection to the winter elements.

Step 3: Add compost activators

Add a compost activator. These are substance that heat up the compost. Popular choices include alfalfa, cottonseed, soybean, bone, and blood meals. Coffee grounds and rabbit manure are also good choices.

Continue feeding the bin throughout the winter. The process of decomposition creates heat so scraps and brown material will both insulate and heat up the bin. 

If there are not many scraps in the winter, go to local coffee shops or grocery stores and ask for their waste. Many stores will happily provide old fruit and vegetables or used coffee grounds. Card board boxes and newspapers can be torn up and put into the bin to supply the needed amount of brown material and are given away by many companies. 

Step 4: Let go dormant

As the temperature becomes colder, decomposition will slow down and sometimes stop even in the most insulated bins. This is okay.

Continue feeding the bin and allow the weather to warm. Once temperatures rise, the bin will begin decomposition.