Compost Density

• When compost becomes compacted, the conditions inside the compost bin become oxygen poor. The Compost Bin website recommends adding bark mulch, or a similarly bulky material, to break up the compost's contents so that oxygen can flow through it. Churn the compost pile to increase the oxygen flow and prevent odors from developing inside the bin.
  
  

Moisture Control

• Excess moisture will create a foul odor inside your compost bin. Although organic matter requires moisture in order to break down, too much will actually prevent decomposition. To absorb excess moisture, mix sawdust, manure, leaves or hay into compost.
  
  

Appropriate Contents

• An efficient compost bin will not produce foul odors. To prevent odors, do not compost meat, dairy and fatty or oily foods. In addition to mixing compost regularly, keep compost moist, dismantle larger pieces of organic matter and add soil to keep your compost functioning properly and odor free.