Four key points of fertilization for protected vegetables in winter

Because of the low external temperature in winter, it is difficult to manage the production of protected vegetables, especially in the aspect of fertilization, if the method is improper, it will often have a great impact on the growth of protected vegetables. The following introduces the key points of fertilization of facility vegetables in winter for vegetable farmers' reference.

1. Heavy application of base fertilizer

The principle of adequate application of base fertilizer and less topdressing should be grasped in production. In general, the proportion of base fertilizer should account for about 70% of the total fertilizer application, in which phosphate fertilizer can be increased to 70% due to slow decomposition, and the topdressing of nitrogen and potassium should be 50%. High-quality farm compost and barnyard manure must be fully mature, the amount of high-quality compound fertilizer per mu is about 5000 kg, and the general amount of high-quality compound fertilizer is 75 kg per mu. The rest of topdressing should be flexibly mastered according to the growth of vegetables and the regular period of fertilizer demand.

II. Balanced fertilization

The nutrition of organic fertilizer is comprehensive and balanced, which can not only improve the soil, improve the ability of fertilizer and water conservation, but also make the fertilizer release steadily, and adjust the pH of the balanced soil. In addition to the application of farm-made fertilizer, the application of bio-organic fertilizer or bacterial fertilizer should also be vigorously promoted. This kind of organic compound fertilizer can provide a large number of element fertilizers, a variety of trace elements, add organic matter to improve soil, restrain the harm of some diseases and pests in soil, and avoid fertilizer damage caused by centralized supply of soil fertilizer.

Third, deep application of trenching

Due to the high degree of airtightness of vegetables in greenhouse, shallow fertilization or sprinkling fertilizer is very easy to make fertilizer volatilization, which not only reduces fertilizer efficiency but also easily produces ammonia to harm vegetables. When topdressing, one important point or strip application, the depth is 5cm to 6cm, and the second is to maintain a distance of 8cm to 10cm from the root system of vegetables.

4. Master the appropriate temperature

Nitrogen fertilizers such as urea and ammonium bicarbonate are easily absorbed and utilized by vegetables only when they are converted into nitrate nitrogen, and the external cause of absorption speed is the temperature condition. When the indoor temperature is lower than 15 ℃, the activity of nitrifying bacteria will be inhibited. Therefore, topdressing nitrogen fertilizer should be carried out around noon on a sunny day, too early or too late will reduce the effect of topdressing because of low temperature. After watering and fertilizing, it is necessary to release air and dehumidify at 2: 00 to 3: 00 p. M.

Wang Hu of Dingzhou Agricultural Bureau