Why must bio-organic fertilizer undergo a fermentation and maturation (composting) process?

Many farmers, when purchasing bio-organic fertilizer, often wonder: since the raw materials—such as livestock manure, crop straw, and fungal residue—are already organic matter, why can’t they be applied directly to the fields without undergoing fermentation and maturation? Maturation is an essential core stage in the production of bio-organic fertilizer; it directly determines the safety of the fertilizer, its efficacy, and its performance in the soil. A bio-organic fertilizer production line equipped with a compost turning machine (compost turner) is the key system used to carry out this critical process.

Using unmaturated organic materials poses significant risks. Raw livestock manure and crop straw often contain large numbers of insect eggs, pathogens, and weed seeds. If applied directly to the soil, these materials may undergo secondary fermentation, causing localized temperatures to spike. This can easily scorch crop roots, leading to root damage or the rotting of seedlings. Furthermore, unmaturated materials continue to consume nitrogen from the soil—a phenomenon often described as "competing with crops for nitrogen"—which results in short-term nitrogen deficiency and stunted crop growth. Additionally, raw manure contains harmful gases like ammonia and hydrogen sulfide, which produce pungent odors, inhibit seed germination, and pollute the field environment.

The fermentation and maturation process essentially utilizes beneficial microorganisms to break down and transform organic materials. Under optimal conditions of moisture, temperature, and oxygen, these microorganisms remain active, degrading complex macromolecules like cellulose and proteins. They convert coarse organic matter—which is difficult for crops to absorb—into small-molecule, bioactive nutrients such as humic acids and amino acids. This shifts the nutrients from a slow-acting state to a sustained-release form, allowing crop roots to absorb them steadily over a longer period, thereby ensuring more durable fertilizing effects.

The maturation stage is also crucial for eliminating harmful substances. During the high-temperature aerobic fermentation phase, the temperature of the compost pile can reach and sustain levels above 55°C. This effectively destroys most parasite eggs, pathogenic bacteria, and weed seeds, thereby reducing the incidence of soil-borne diseases. Once fermentation is complete, the material becomes loose in structure and odorless; it will no longer undergo anaerobic fermentation in the soil to produce harmful substances, making it significantly safer for agricultural use. Furthermore, fully decomposed organic fertilizer creates a more favorable environment for the survival of functional microorganisms. High-quality bio-organic fertilizers are enriched with beneficial functional microbes; however, raw, undecomposed materials—characterized by high ammonia levels, elevated temperatures, and oxygen-depleted conditions—will effectively kill these beneficial organisms. A well-decomposed, stable substrate maintains a moderate pH, providing a stable habitat for beneficial microorganisms such as *Bacillus subtilis* and actinomycetes. Once established in the soil, these live microbes help improve soil structure, solubilize phosphorus and potassium, and suppress harmful pathogens.

In short, the fermentation and decomposition process is not merely a matter of piling up organic matter; it is an essential stage for ensuring safety, facilitating nutrient transformation, and preserving the viability of functional microorganisms. Bypassing this process by applying raw organic materials may appear cost-effective, but it frequently leads to fertilizer burn and the spread of diseases—a counterproductive outcome. Only when organic matter is thoroughly decomposed can bio-organic fertilizer be safely returned to the land, where it can continuously improve soil aggregate structure, enhance soil fertility, and support stable crop yields and superior produce quality.