Improper fertilization to aggravate diseases and greenhouse diseases

 At present, many vegetable greenhouses cause burned seedlings and increased disease due to improper fertilization. According to the expert's typical experience of scientific fertilization of greenhouse vegetables, greenhouse vegetable cultivation should pay attention to five points in fertilization:

Greenhouse vegetable fertilization

First, the appropriate amount of fertilizer
  Because greenhouses have protective facilities, the soil cannot be fully washed by rainwater, and fertilizers are not easily lost. Therefore, excessive application of chemical fertilizers can easily cause salt to accumulate on the surface of the soil, lightly affect the growth of vegetables, and cause soil salinization. Therefore, before fertilizing, soil nutrients must be diagnosed, a rational formula fertilization plan should be formulated, and the quick-effect fertilizer should be applied in excess to prevent blindness.

Second, pay attention to potassium fertilizer:
  The application of potash fertilizer in melons and solanaceous vegetables has obvious effect on yield increase. This is due to the partial application of nitrogen and phosphorus fertilizers in greenhouses with greenhouse vegetables. As a result, the soil potassium supply decreases with the increase of planting years and the increase of vegetable yield. According to the experiment, cucumbers in the greenhouses and 7.5 kg of potassium oxide were applied to the sheds, showing that the stems are thick, the leaves are bright green and thick, and the melon strips are straight. In winter, the Chinese cabbage has an obvious increase in yield and quality. It should be noted that when using potash fertilizers, it is best not to use potassium chloride to avoid soil salinization.

Third, a small amount of fertilizer:
  Vegetables need more fertilizer, in addition to the application of full-body fertilizer, but also need topdressing, top dressing, it should be a small number of times, so that can prevent the loss of nutrients, and can give full play to fertilizer efficiency, improve fertilizer utilization.

Fourth, the lack of nutrient supplements:
  Although the demand for microelements in vegetables is small, micronutrients are indispensable nutrients involved in the physiological effects of vegetables. For example, if the trace elements in the soil are insufficient, the vegetables will have different symptoms of deficiency, and the yield will decrease and the quality will decline. If the content of trace elements in the soil is too much, it will cause vegetable poisoning, which also causes a decrease in production and quality. Therefore, the application of trace element fertilizer must be based on soil test results and the lack of vegetables, and must be based on the principle of lack of fill.

Fifth, the top-dressing fertilizer should be accurate:
  Foliar spray fertilizer method is simple, save time and labor, can avoid excessive water caused by excessive soil moisture resulting in increased disease susceptibility of vegetables, but also quickly add nutrients, but to grasp the application concentration, otherwise easy to produce fertilizer damage, “ Burning leaves, generally foliar spraying fertilizer concentration: urea 1%, potassium dihydrogen phosphate 0.2~0.5%, diammonium phosphate 1%, zinc sulfate 0.1~0.2%, manganese sulfate 0.1~0.2%, borax 0.1~0.2% Ammonium molybdate 0.05 to 0.1%, copper sulfate 0.02 to 0.2%, and ferrous sulfate 0.2 to 1%.