What Is the Difference Between Layered Composting and Turned Composting?

1. Fundamental Differences in Core Definitions and Operational Modes Layered composting is essentially a static composting method. Its core concept is “layered stacking, natural fermentation.” During operation, materials are not mixed but are stacked in specific layers, much like making a layer cake. Typically, the bottom layer consists of coarse straw or small branches for aeration (about 10-15 cm thick) to ensure ventilation at the base. Above this, layers are alternated: high-carbon material layers (e.g., straw, sawdust, 15-20 cm thick), high-nitrogen material layers (e.g., livestock manure, kitchen waste, 5-10 cm thick), and a thin inoculation layer (mature compost or commercial microbial agents, 2-3 cm thick). This process is repeated until the pile reaches a height of about 1.2-1.5 meters, and is finally covered with a layer of soil or breathable film to retain heat and moisture. The entire process requires little to no turning, relying primarily on natural air convection and microbial diffusion within the pile structure to complete fermentation. In sharp contrast, turned composting is a dynamic composting method. Its core lies in “thorough mixing and active aeration.” All raw materials are crushed and thoroughly mixed to achieve an ideal carbon-to-nitrogen ratio (typically 25:1 to 30:1) and moisture content (55%-60%) before piling. The mixed materials are then formed into long, windrow-shaped piles. Regular, mechanical turning is employed to force aeration. When the core temperature rises to the thermophilic stage of 55-65°C, the pile is turned every 2-3 days using a compost turner. This process moves the inner materials to the outside and the outer materials to the inside, ensuring even oxygen distribution, controlled temperature, and promoting uniform maturation throughout the pile.

Click to Visit Site