The flowering period is the peak of broad bean fertilizer requirement, broad bean fertilizer requirement law and fertilizer application method.

Broad bean needs more fertilizer, such as nitrogen, phosphorus, potassium, calcium, etc., flowering period is the peak period of broad bean fertilizer, dry matter accumulation is the most. In addition, broad bean demand for trace elements, molybdenum, boron sensitive response, should pay attention to broad bean boron deficiency, there are "phosphorus-loving crops" said. The ratio of N, P and K uptake in the whole growth period was about 1∶0.5∶0.6. To produce 100 kg of broad bean, it needs to absorb 4.45 - 4.80 kg of pure nitrogen, 1.09- 1.40 kg of P2O5 and 1.66 - 2.10 kg of K2O. Due to the nitrogen-fixing effect of Rhizobium fabae, about 2/3 of the nitrogen required can be solved by itself.

top dressing of broad bean

1. Absorption of nitrogen, phosphorus and potassium at different growth stages:

The absorption of nitrogen, phosphorus and potassium varies with the growth period of broad bean. From the growth stage analysis, the early stage of broad bean rhizobia has not yet multiplied and nitrogen fixation, a small amount of nitrogen needs to be supplied, but phosphorus, potassium, calcium, boron and other elements are urgently needed. Before branching stage, the nutrient uptake was 20%, at bud stage, 20%, at flowering and pod stage, the growth and development was fast, and the nutrient uptake was the most, accounting for 60% of the whole growth period.

II. Scientific fertilization technology:

Broad bean fertilization, adhere to the application of organic fertilizer on the basis of combined application of chemical fertilizer; nitrogen, phosphorus, potassium combined application. Fertilization, must be heavy base fertilizer, increased phosphorus fertilizer, nitrogen fertilizer to see seedlings, flower pod fertilizer. On the basis of applying enough basal fertilizer, topdressing is done well, and the basal fertilizer is mainly phosphorus and potassium fertilizer; topdressing is mainly nitrogen fertilizer, and it is applied at one time during flowering and pod-bearing period. In the later stages of growth, fertilizer is generally no longer applied. N: P 2O 5: K 2O =4:5:6.

Third, the application of organic fertilizer:

During the whole growth period of broad bean, the fertilizer application amount per mu is 1000-1500 kg of decomposed organic compost, which is applied as base fertilizer at one time during soil preparation.

IV. Rational determination of nitrogen, phosphorus and potassium application rates:

N fertilizer application rate is 3- 4 kg, P 2O 5 4-5 kg and K 2O 5-6kg per mu during the whole growth period of broad bean. Phosphate fertilizer and potassium fertilizer are used as base fertilizer and applied at one time; nitrogen fertilizer is used as flower and pod fertilizer at the early stage of flowering and pod bearing and applied at one time.

1. Base fertilizer. In order to improve the soil structure, ensure that the bean seedlings are uniform, complete and strong, and lay the foundation for branching, flowering, pod setting and high yield, calcium superphosphate 25-31.25kg and potassium chloride 9.26-11.1kg are applied as base fertilizer in one time in combination with soil preparation.

2. Topdressing. 6.5-8.7kg urea per mu is applied as flower and pod fertilizer at the early stage of flowering and pod setting.

5. Targeted application of micro-fertilizer:

According to the growth characteristics and fertilizer requirements of broad bean, boron fertilizer and molybdenum fertilizer should be supplemented. Borax 0.5- 1kg per mu is used as base fertilizer, and ammonium molybdate 0.3-0.4kg is applied in the branching stage or flowering and pod stage.

VI. Proper lime application for acidic field blocks:

The suitable soil pH value for broad bean growth is 6.2-8. Acidic field blocks, proper application of lime, can adjust soil pH, supplement calcium fertilizer and soil disinfection sterilization, conducive to the normal growth and development of broad beans, improve yield. 66.7kg lime powder was used for one-time application per mu during soil preparation.

VII. Spraying foliar fertilizer:

Flowering and pod stage is the peak period of fertilizer demand of broad bean, so foliar fertilization should be carried out in time. 0.2%-0.3% potassium dihydrogen phosphate solution should be sprayed on foliar surface at bud stage and flower and pod stage respectively to increase seed weight and yield.