How To Make Healthy Compost

Managing the Decay Process

You can affect the speed of the composting process and the quality of the compost product by managing the factors described below.
Food (raw materials). For fast composting, the initial mix must have the proper moisture and air content, and organic materials that provide a rich food (energy) source for bacteria. A list follows of some materials commonly used in making compost. They are separated into “energy” materials, “bulking agents,” and “balanced” materials.

Compost Raw Materials Table

Bulking agents
(low moisture, high porosity, low nitrogen) 
• wood chips
• sawdust
• grass hay
• wheat straw
• corn stalks
Energy materials
(high moisture, low porosity, high nitrogen)
• grass clippings
• fresh dairy, chicken or rabbit manure
• fruit and vegetable waste
• garden trimmings
Balanced raw materials
(low to medium moisture, medium porosity, medium nitrogen) 
• Ground tree and shrub trimmings
• Horse manure and bedding
• Deciduous leaves
• Legume hay

Energy materials provide the nitrogen and high-energy carbon compounds needed for fast
microbial growth. If piled without bulking agents, these materials usually are too wet and dense to allow much air into the compost pile. When you open the pile, it will have a foul, “rotten egg” smell.
Bulking agents are dry, porous materials that help aerate the compost pile. They are too low in moisture and nutrients to decay quickly on their own.
Balanced raw materials Some raw materials contain a balance of energy and bulking agent
properties. These materials will compost readily without being blended with other ingredients. Examples include horse manure mixed with bedding, spoiled alfalfa hay, and deciduous leaves. These materials are handy for ensuring the success of hot compost piles.

TIP: Grinding, cutting, smashing, or chopping raw materials reduces particle size.
Small particles have more surface area for microbial activity and are easier to mix.