N ratios for commonly used materials. Back To Top Table 1. In general, coarse, dried-out materials contain little nitrogen. With experience, composters develop procedures resulting in workable mixtures for materials available. Particle size .
Microbial activity occurs on the surface of particles.
Breaking particles into smaller pieces allows the microorganisms to digest more material, multiply faster, and generate more heat. Chopping, shredding or chipping materials accelerates the composting process. Aeration replaces oxygen-deficient air in the center of the compost pile with fresh air. Rapid aerobic decomposition occurs only when there is enough oxygen present. Air movement throughout the compost pile is affected by spaces between particles in the compost pile and by moisture content.