Key points for safe fertilization in vegetable cultivation

   Pollution-free vegetable cultivation, especially greenhouse cultivation of pollution-free vegetables, pay attention to the following seven points fertilization: 

   

    First, chemical fertilizers in moderation 

   

    However, the amount of fertilization, the shed indoor fertilizer is not easy to lose, excessive application of chemical fertilizer is likely to cause the increase of salt concentration in the soil, which affects the normal growth of vegetables, and the secondary salinization of the soil. Therefore, fertilization must be carried out before fertilization, scientific and rational fertilization should be carried out, and blind fertilization should not be avoided. 

   

    Second, the full maturity of organic fertilizer to prevent the resulting ammonia, poisoned vegetables 

   

    Unfertilized organic fertilizers often carry germs and eggs, which cause harm to vegetables. In addition, if the organic fertilizer is further decomposed in the greenhouse, ammonia "burn" seedlings will be produced. Therefore, the organic fertilizer should be fully decomposed and then applied.

   

    Third, the fertilization method is appropriate, do not scatter

   

    The base fertilizer is preferably applied 1 week before planting and mixed evenly with the soil. Topdressing can be applied at a distance of about 8 cm from the plant or applied to the hole. After application, the soil is covered and watered. The fertilizer can also be applied with water at a certain concentration. Do not spray fertilizer, especially nitrogen fertilizer, directly on the surface or on the plant, which can easily cause nutrient loss and “burn” vegetables. 

   

    Fourth, the foliage should be timely, do not fertilize  in bright light

   

    The best time for top dressing outside vegetable roots: 

   

    At the peak of the fertilizer demand for vegetables, when the soil nutrient supply is insufficient. 

   

    In the late growth stage of vegetables, when the root absorption capacity is weakened. The top dressing should be carried out on a cloudy day or in the evening. Do not carry it out when the sun is strong at noon. The fertilizer should be sprayed on the back of the new leaves and leaves as much as possible to facilitate the absorption of vegetables. Foliar fertilization should be based on the nutritional characteristics of vegetables, the symptoms of lack of fertilizer and the ability of soil fertility to be targeted.

   

    Fifth, the application of fertilizer in moderation, not excess 

   

    Although the amount of trace elements used in vegetables is small, it plays a large role in vegetable metabolism. There are many types of trace element fertilizers, such as boron, molybdenum and iron fertilizer. Trace element fertilizers are used as base fertilizers, and can also be used for seed dressing, soaking seeds and top dressing. The range between the amount of micro-fertilizer and the excess is relatively narrow, and the dosage must be accurate. Excessive application of micro-fertilizer can cause fat damage.

   

    Six, carbon dioxide gas added to the appropriate fertilizer 

   

    Carbon dioxide is the main raw material for plant photosynthesis, and it is necessary to properly supplement carbon dioxide in greenhouse vegetable production. If the greenhouse lacks carbon dioxide, the plants cannot perform photosynthesis and cannot grow. At present, the use of ammonium bicarbonate and concentrated sulfuric acid to produce carbon dioxide, carbon dioxide fertilization of boron room vegetables, is a simple, easy, low cost, convenient method. 

   

    Seven, using a plant growth regulator to properly 

   

    The proper use of plant growth regulators is unmatched by conventional techniques. However, each regulator has certain conditions and scope in application, especially to strictly control the use time and concentration. If used improperly, it will be counterproductive.