Beans do not have high requirements for fertilizers. In the early stage of plant growth (podging stage), due to the insufficient development of nodules and weak nitrogen fixation capacity, nitrogen fertilizer should be supplied in an appropriate amount. After flowering and pod formation, the plant's demand for phosphorus and potassium elements increases, and the nitrogen-fixing ability of the rhizobia is enhanced. During this period, due to the vegetative growth and reproductive growth, the demand for various nutrients increases.

Related research shows that for every 1000 kg of beans produced, 10.2 kg of pure nitrogen, 4.4 kg of phosphorus pentoxide, and 9.7 kg of potassium oxide are required. However, due to the nitrogen-fixing effect of rhizobia, potassium nutrients are required during the growth of bean, and phosphorus nutrients Secondly, nitrogen nutrition is relatively small. Therefore, the water and fertilizer should be properly controlled in the cultivation of beans, the appropriate amount of nitrogen should be applied, and phosphorus and potassium fertilizers should be added.

1. Reapply base fertilizer:

For continuous crops of beans, it is best to choose plots that have not been planted with cotton and legumes within three years. The base fertilizer is mainly organic fertilizer, combined with the application of appropriate proportion of compound and mixed fertilizers, such as 15-15-15 pure sulfur base, etc. Similar high-phosphorus, potassium compound and mixed fertilizers are more suitable for the selection of bean base fertilizer.

  2. Apply topdressing skillfully: 

After planting, squat seedlings are the main ones to control the length of stems and leaves and promote reproductive growth to form more inflorescences. After scab formation, combined with watering and ditching, top-up 15000 kg/ha of decomposed organic fertilizer or 20-9-11 sulfur-containing compound fertilizer and other similar compound and mixed fertilizers of 75～120 kg/ha, every subsequent harvest Two pod top dressings and one fertilizer, 75-150 kg/ha for urea, 75-120 kg/ha for potassium sulfate, or 120-180 kg/ha for compound fertilizers such as 17-7-17 sulfur-containing compound fertilizer.

In addition, in the peak growth period, according to the current status of the growth of beans, 0.3% potassium dihydrogen phosphate is used for foliar fertilization at the appropriate time, and in order to promote the early symbiotic nitrogen fixation of bean nodules, nitrogen-fixing bacteria can be used for seed dressing.