Description: Derived naturally from plant or animal matter, these fertilizers release nutrients gradually as they break down. They improve soil structure, stimulate beneficial microbial life, and enhance long-term moisture retention.

Common Sources: Compost, manure, bone meal, blood meal, seaweed extract, and guano.

Best Used For: Sustainable agriculture, organic farming compliance, improving degraded soils, and minimizing the risk of chemical nutrient burn.