Managing Your Three-Bin Compost System

For those of you that have ventured into the world of the three-bin composting system, here are some tips and tricks to help you stay ahead of your compost.

1. Add yard waste to one of the end bins. Mix in "green" materials like grass clippings or other fresh plant waste with "brown" materials like dried leaves, wood chips or shredded branches. 
2. Add a layer of garden soil to introduce some of the microorganisms that do the composting. Once the composting process is under way, it is not necessary to add more soil. 
3. With this hot composting method, check the temperature of the compost from time to time with a compost thermometer. The pile should be warm in the middle. After the middle has reached 140 to 150 F, turn the pile from the original bin into the adjacent center bin.
   Close monitoring of the temperature is essential only for the most rapid composting since the process will go on at varying rates even if close attention is not given to temperature. 
4. Additional yard waste can be placed on the recently turned compost, but turn the pile back into the original end bin when the temperature has been up around 150 degrees. 
5. Turning should be repeated whenever the temperature gets high enough. Over time, less frequent turning will be needed, and the composted material can be held in one of the end bins until you are ready to use it in the yard or garden. 
6. Repeat the process using the vacant end bin and alternate turning between that bin and the center bin. 
7. Use the compost in the original end bin until it is gone; then you can start the composting process again in the vacated end bin. 
8. Once set up, the three-bin composting system will consist of one bin with yard waste being composted; one bin empty, to or from which the compost is turned; and one bin containing finished, or nearly finished, compost. 

Nearly 1 cubic yard of compost can be produced per bin in the three- bin composting system. However, the rate of composting differs greatly according to the kinds of materials placed in the system and the precision with which you manage the composting process.  Compost is ready to use when it is dark brown, crumbly, and earthy-smelling.

(Source: University of California Cooperative Extension)