Organic fertilizer refers to fertilizer derived from animal and plant residues, excrement or other organic matter. Unlike chemical fertilizers, organic fertilizer not only provides nutrients needed for plant growth, but also improves soil structure and enhances soil biological activity. It is an important part of sustainable agriculture and is known as the “vitamin of soil”.
- Sources and classification of organic fertilizers
The sources of organic fertilizers are very wide, mainly including the following categories:
a. Animal organic fertilizers: such as livestock and poultry manure, fish meal, bone meal, etc.
b. Plant organic fertilizers: such as straw, green manure, bean cake, etc.
c. Microbial organic fertilizers: fertilizers made by microbial fermentation such as compost and biogas slurry.
d. Industrial by-products: such as sugar factory waste residue, distiller’s grains, etc.
These fertilizers can provide rich organic matter and trace elements to the soil after natural decomposition or artificial treatment.
- Mechanism of action of organic fertilizers
a. Improve soil structure: Organic matter in organic fertilizers can promote the formation of soil aggregate structure, enhance soil permeability and water retention.
b. Provide nutrients: Organic fertilizers contain macroelements such as nitrogen, phosphorus, potassium, and trace elements such as calcium, magnesium, and sulfur, which can meet the needs of plant growth.
c. Enhance microbial activity: Organic fertilizers are “food” for soil microorganisms, which can promote the reproduction of microorganisms, thereby accelerating the decomposition of organic matter and the release of nutrients.
d. Reduce environmental pollution: Compared with chemical fertilizers, the use of organic fertilizers can reduce the risk of soil compaction and eutrophication of water bodies.
- Methods of making organic fertilizers
a. Composting method: Mix animal and plant residues, kitchen waste, etc. and pile them up to make them mature through the action of microorganisms. During the composting process, attention should be paid to turning the pile and moisturizing to accelerate decomposition.
b. Biogas fermentation method: Use biogas tanks to perform anaerobically fermented organic waste, and the resulting biogas liquid and biogas residue are high-quality organic fertilizers.
c. Vermicomposting method: Use earthworms to decompose organic waste, and the earthworm excrement (worm manure) is an efficient organic fertilizer.
- Tips for using organic fertilizers
a. Combination of basal fertilizer and topdressing: Organic fertilizers can be applied to the soil as basal fertilizer before planting, or as topdressing during plant growth.
b. Appropriate application: Although organic fertilizers are friendly to the soil, excessive use may also lead to nutrient imbalance. Generally, 2-3 tons per mu of land is appropriate.
c. Combine with other fertilizers: Organic fertilizers can be used in combination with a small amount of chemical fertilizers or biofertilizers to achieve better results.
- Advantages and challenges of organic fertilizers
a. Advantages:
Environmentally friendly and sustainable, reducing dependence on chemical fertilizers.
Improve soil health and improve crop quality.
The cost is low and suitable for small farmers.
b. Challenges:
Nutrients are released slowly and the effect is not as fast as chemical fertilizers.
A large storage and transportation space is required.
The production process may produce odors, which need to be managed carefully.
- Future development trends of organic fertilizers
With people’s attention to food safety and environmental protection, the market demand for organic fertilizers is growing rapidly. In the future, the development of organic fertilizers will show the following trends:
a. Technological innovation: Improve the nutrient content and release efficiency of organic fertilizers through the improvement of microbial technology and fermentation process.
b. Large-scale production: The establishment of large-scale organic fertilizer factories will solve the quality control problems in small-scale production.
c. Policy support: Governments are introducing policies to encourage the use of organic fertilizers and promote the development of green agriculture.
Organic fertilizers are precious resources given to us by nature. They can not only nourish crops, but also repair soil and protect the environment. Whether it is home gardening or large-scale agriculture, the rational use of organic fertilizers can bring significant economic and ecological benefits. Let us embrace organic agriculture and contribute to the sustainable development of the earth!
