Get rid of the misunderstanding of foliar fertilizer spraying

Foliar fertilization, also known as foliar spraying. It means that the non-toxic and harmless organic or inorganic nutrient solution containing various nutrients is sprayed on the leaf surface of the plant according to a certain dose and concentration, which plays the role of supplying nutrients directly or indirectly, which is called foliar fertilizer spraying, also known as extra-root topdressing.

Foliar spraying fertilizer is simple and easy, the use of fertilizer is less, the fertilizer effect is fast, and the yield is significant. According to the analysis of statistical data, in general, timely spraying the necessary nutrients on crop leaves on moderately fertile soil can increase the average yield of grain crops by 5-10%, fruit trees by 5-15%, and vegetables by 20-30%. However, in some places, due to improper understanding or application, the application effect is not good, and even into a misunderstanding, which is not only disadvantageous to production, but also cause losses.

I. arbitrary spraying

It is mistakenly believed that foliar fertilizer can be sprayed at any growth stage of the crop. Foliar fertilizer is absorbed by leaves, which requires crops to have sufficient leaf area, otherwise the effect of spraying is poor and can not achieve the goal. Therefore, fertilizer spraying should generally be carried out in the middle and later stages of crop growth in order to obtain the maximum benefit of foliar fertilizer spraying.

2. Arbitrary use of fertilizer

Mistakenly think that any fertilizer can be used as foliar fertilizer. In fact, some volatile fertilizers, such as ammonia, ammonium carbonate, etc., volatilize ammonia after spraying, which will cause fumigation to the crops. The other is some crop taboo fertilizers, such as potassium chloride, calcium chloride, etc., should not be sprayed on crops such as tobacco.

Third, spray at any time

Mistakenly thinking that it can be done at any time. If after rain or early in the morning, when there are water or dew on the leaves, it is not suitable to spray fertilizer, otherwise it will reduce the spraying concentration, can not meet the concentration requirements, and the effect is poor. Avoid spraying in the hot sun at noon on a sunny day, because it can not maintain a moist state for a long time after spraying, the absorption of leaves is poor, and the utilization rate is reduced.

4. High concentration and good effect

Mistakenly thought that the higher the concentration of spraying, the better the effect. Foliar fertilization only plays a supplementary and regulatory role, and can not replace soil fertilization. The concentration of fertilizer should be strictly controlled. In the suitable range of use, the general concentration of spraying should be low rather than high. However, different crops have different fertility tolerance and different requirements; different kinds of fertilizers and different concentrations of fertilizer are sprayed. Too low concentration can not reach the effect of fertilizer spraying; if the concentration is too high, it often dehydrates the leaves and causes fertilizer damage. This is one of the keys to the success or failure of foliar fertilizer spraying. For example, when urea is used as foliar fertilizer, the concentration is generally 0.5% Mel 2.0%; calcium superphosphate is 1% Mel 5%; potassium dihydrogen phosphate is 0.2% Mel 0.5%; Boric acid is 0.1% MAE 0.5%; amine molybdate is 0.02% MUE 0.05%; Zinc Sulfate is 0.05% PUE 0.2%. At the same time, it is necessary to grasp that the concentration of spraying at the seedling stage should be appropriately lower; the concentration of spraying in the middle and later stages of growth should be appropriately higher; when crops grow normally, the concentration should be lower, and when there is a deficiency of fertilizer, the concentration of trace element fertilizer should be lower; the concentration of major element fertilizer should be appropriately higher; the concentration of dicotyledon spraying should be lower; and the concentration of Monocotyledon spraying should be appropriately higher.

Fifth, random mixed application

Mistakenly think that no matter what kind of fertilizer or pesticide can be mixed and sprayed at will.

6. Increase the frequency of spraying

Mistakenly think that the more times foliar fertilizer is sprayed, the better. The crops with short growth period are generally sprayed 1-2 times, and those with long growth period can be sprayed 2-3 times. It can also be sprayed 1-2 times according to the soil fertility of the seedlings. It should be sprayed continuously in the same growth period with an interval of about 10 days each time. Spray trace element fertilizer, spray once, want to spray the second time, the interval should be lengthened.