Organic fertilisers include farmyard manure, such as solid manure, slurry, and liquid manure, as well as green manure, straw, compost, and other processed organic materials. Nutrients in organic fertilisers occur primarily in organic forms and originate from plant residues, animal excreta, and other biological sources. During decomposition in the soil, nutrients such as nitrogen, phosphorus, and potassium are released and converted into forms available for plant uptake. Organic fertilisers contribute to increasing soil organic matter content, improving soil structure, and stimulating soil biological activity. Their application is essential for maintaining soil fertility and supporting sustainable agricultural production.