Fertilizer demand pattern:

The Fertilization Characteristics and Scientific Fertilization of Beans. Beans, also known as cowpeas, long cowpeas, or legumes, belong to the legume family and are annual vegetables. Beans are rich in protein, carotene, high in nutritional value, and have a good taste. They are one of the popular vegetables widely cultivated in the north and south of China, and their popularity ranks first among various vegetables. Beans have strong adaptability and can be cultivated in both open fields and protected areas. They can also be produced annually and are available for sale all year round.

The Fertilization Characteristics of Soybeans

The root system of beans is relatively developed, but their regeneration ability is relatively weak. The depth of the main root entering the soil is generally between 80-100 centimeters, and the group roots are mainly distributed in the cultivated layer of 15-18 centimeters. The lateral roots are sparse, and the root nodules are also relatively few, resulting in relatively weak nitrogen fixation ability. Bean root systems have a wide adaptability to soil, but fertile, well drained, and well ventilated soil is preferred. Soil that is too sticky and low humidity is not conducive to root growth and nodule activity.

Beans do not have high requirements for fertilizers. In the early stage of plant growth (podding stage), due to the insufficient development of root nodules and weak nitrogen fixation ability, nitrogen fertilizer should be supplied in moderation. After flowering and podding, the plant's demand for phosphorus and potassium elements increases, and the nitrogen fixation ability of rhizobia is enhanced. During this period, due to the coexistence of nutritional and reproductive growth, the demand for various nutrients increases. Related studies have shown that for every 1000 kilograms of beans produced, 10.2 kilograms of pure nitrogen, 4.4 kilograms of phosphorus pentoxide, and 9.7 kilograms of potassium oxide are required. However, due to the nitrogen fixation effect of rhizobia, the growth process of beans requires the most potassium nutrition, followed by phosphorus nutrition, and relatively less nitrogen nutrition. Therefore, in bean cultivation, water and fertilizer should be appropriately controlled, nitrogen should be applied appropriately, and phosphorus and potassium fertilizers should be increased.

Achieve scientific fertilization

Based on the above explanation of the root absorption characteristics and fertilizer demand characteristics of beans, combined with current cultivation techniques of beans, the scientific fertilization methods of beans are summarized as follows:

1. Heavy application of base fertilizer: Soybeans should avoid continuous cropping, and it is best to choose plots that have not planted cotton or leguminous plants within three years. The base fertilizer should mainly be organic fertilizer, combined with appropriate ratios of compound and mixed fertilizers, such as 15-15-15 Stanley pure sulfur based high phosphorus and potassium compound and mixed fertilizers, which are more suitable for use as base fertilizer for beans. It is worth noting that when applying base fertilizer, the amount of fertilization should be increased or decreased appropriately according to the local soil fertility.

2. Skilled fertilization: After planting, the main method is to squat the seedlings, control the elongation of stems and leaves, promote reproductive growth, and form more inflorescences. After scabbing, combined with watering and trenching, apply 15000 kg/ha of decomposed organic fertilizer or similar compound or mixed fertilizers such as 20-9-11 sulfur-containing compound fertilizer with a weight of 75-120 kg/ha. Afterwards, apply urea with a weight of 75-150 kg/ha, potassium sulfate with a weight of 75-120 kg/ha, or similar compound fertilizers such as 17-7-17 sulfur-containing compound fertilizer with a weight of 120-180 kg/ha every two harvests of pods. To prevent premature aging of plants, after the first peak of yield occurs, it is necessary to pay attention to fertilizer and water management, promote the germination of lateral branches and the formation of lateral flower buds, and allow the original inflorescence on the main vine to continue to bloom and pod.

In addition, during the peak growth period, according to the current growth status of the bean, 0.3% potassium dihydrogen phosphate should be used for foliar fertilization in a timely manner. At the same time, to promote early symbiotic nitrogen fixation of bean root nodules, nitrogen fixing bacterial agents can be used for seed dressing.