Checkpoints for Finished Compost
There are several checkpoints to help you gauge the success of your compost. These points will serve as a standard from which you can determine the efficiency of your composting methods:
Structure. The material should be medium loose, not too tight, not packed, and not lumpy. The more crumbly the structure, the better it is.
Color. A black-brown color is best; pure black, if soggy and smelly, denotes anaerobic fermentation with too much moisture and lack of air. A grayish, yellowish color indicates water-logged conditions.
Odor. The odor should be earthlike, or like good woods soil or humus. Any bad smell is a sign that the fermentation has not reached its final goal and that bacterialogical breakdown processes are still going on. A musty, cellarlike odor indicates the presence of molds, sometimes also a hot fermentation, that has led to losses of nitrogen.
Mixture of raw materials. The proper mixture and proportion of raw materials is most important! Indeed, it determines the final outcome of a compost fermentation and the fertilizer value of the compost. On the average, an organic matter content of from 25 to 50 percent should be present in the final product.
Moisture. Most composting failures result from a failure to maintain the proper moisture conditions. Moisture content should be like that of a wrung-out sponge: No water should drip from a sample squeezed in your hand, yet the compost should never be dry.