The advantages of applying organic fertilizers in orchards:  1. Organic fertilizers contain abundant and comprehensive nutrients, which no type of chemical fertilizer can match.  2. Organic fertilizers improve soil quality.  3. Organic fertilizers promote microbial activity in the soil, accelerate biological cycles, enhance fruit tree growth, and ensure fruit quality.  4. During decomposition, organic fertilizers generate substantial organic acids, converting insoluble nutrients into soluble ones, thereby increasing soil nutrient utilization.  5. Regular use of organic fertilizers benefits root system development. Applying organic fertilizers to young trees promotes growth, timely fruiting, and early high yields. For mature trees, organic fertilizers strengthen tree vigor, mitigate alternate bearing, boost yields and quality, enhance disease resistance, and improve economic returns.  The optimal period for applying organic fertilizers is **after harvest**. During this time, apple tree roots experience a growth peak. Post-fertilization, root wounds heal quickly, enabling rapid growth and nutrient absorption, which effectively enhances late-season leaf photosynthesis and nutrient storage. This also supports root and shoot growth in the following spring, improving fruit set rates.  In Japan, orchard soil organic matter typically ranges from 3% to 5%, while in the U.S., it can reach 3% to 8%. Scientific research indicates that orchard soil organic matter should not fall below 1%, as lower levels severely impact yield and quality. However, many orchards globally still have organic matter content below 1%.  Orchards with high organic matter content produce uniformly red fruits, with higher soluble solids, aromatic profiles, bright colors, and elevated sugar levels. Studies show that for the same 60 kg of high-potassium fertilizer application per acre, orchards with lower organic matter exhibit reduced sugar content, while those with higher organic matter show increased sugar levels.  Yet, some growers still rely heavily on chemical fertilizers while underapplying organic ones. Prolonged neglect of organic fertilization leads to soil degradation, weakened tree growth, delayed productivity, low yields, poor fruit quality, and diminished economic returns. Thus, organic fertilizers play an irreplaceable and crucial role in orchard tree development.