When to use foliar fertilizer and with what to use it for the best effect, knowing these is enough
As a nutrient supplement for leaves, foliar fertilizers are more and more accepted by farmers. However, most of the foliar fertilizers cannot be used for the value and effect. It is either useless or wasteful.
Foliar fertilization can make nutrients enter the body directly from the leaves and participate in the metabolism of crops and the synthesis of organic matter, so it is more rapid and effective than soil fertilization. Therefore, it is often used as an effective measure for timely treatment of crop deficiency. During fertilization, spraying and supplementary application can also be carried out in stages according to the growth period of the crop and the actual situation of the seedling condition and soil fertilizer supply, and give full play to the characteristics of rapid response of foliar fertilizer to ensure the normal growth and development of crops under suitable fertilizer and water conditions. , to achieve the purpose of high yield.
Supplements the lack of root fertilization
When it is inconvenient to fertilize the roots of crops, such as in the late stage of crop growth, the root vigor declines and the ability to absorb fertilizer is reduced; or when the soil environment is unfavorable for the growth of crops, such as excessive water, drought, soil is too acid, too alkaline, The absorption of the root system of the crops is blocked, and the crops need to recover quickly. If the root application method cannot meet the needs of the crops in time, foliar spraying can quickly supplement nutrients and meet the needs of crop growth and development.
Specifically, the roots of crops are not fully developed at the seedling stage. The nutrient needs of crops can be supplemented by spraying nitrogen, phosphorus and potassium fertilizers on the leaves. At the same time, some growth regulators can be added to promote crop growth.
Before and after flowering, crops have a relatively large demand for phosphorus and potassium. Therefore, at this time, the supplementary elements of leaves are mainly phosphorus and potassium elements, such as phosphorus and potassium source pools. At the same time, the demand for boron is relatively large during the flowering period, and it is necessary to assist the spraying of boron fertilizer.
The demand for nitrogen and potassium is relatively large during the fruit expansion period, and the foliar supplementary nutrients are mainly nitrogen and potassium, such as potassium nitrate. The demand for potassium in the fruit coloring period is relatively large, and the supplementation of leaves is mainly based on potassium fertilizer.
In the late stage of crop growth, the degeneration of the roots reduces the ability of crops to absorb nutrients. Therefore, various nutrients such as nitrogen, phosphorus and potassium need to be supplemented through leaves at this time. For some melon and fruit crops, especially those that require a large amount of calcium, calcium should be intentionally supplemented through leaves from the beginning of fruit setting.
In the process of crop growth, crops have shown some nutrient deficiencies. Because soil fertilization requires a certain period of time for nutrients to be absorbed by crops, the symptoms of crop deficiency cannot be relieved in time. At this time, the use of foliar fertilization can enable nutrients to quickly enter the plant through the leaves and solve the problem of lack of nutrients.
For example: when the tree is weak, the leaves are yellow, and the growth is slow, the plant is deficient in nitrogen. When the tree body is too vigorous, the leaves are large and green, and the internodes are too long, the nitrogen is too rich, and the fertilizer should be mainly phosphorus and potassium.
Pay attention to the timing of spraying
1. The recommended time is morning or afternoon, and noon should be avoided, because the temperature at noon is high, the water evaporates quickly, the fertilizer liquid stays on the leaves for a short time, and the waste is large; secondly, the high temperature at noon may cause damage to fruits and leaves. burns.
2. Pay attention to spraying on the back of the leaves. Because the back tissue is loosely arranged, it is easier to enter the crop body, while the front is more horny, which is more difficult to absorb and easier to evaporate.
Many people have the same foliar fertilizer, and there is no difference in the various contents. This is a wrong perception. The mechanism of leaf supplementation has already been said, when the root supply is insufficient, if you do not supplement as needed, it will cause the lack of supplementation, and the lack of supplementation will become a waste. When supplementing foliar fertilizer, some adhesives, such as washing powder or detergent, can be appropriately added to increase the residence time of the aqueous solution on the surface of the crop, which can improve the absorption and utilization rate of nutrients by the crop.
Pure nutrients will not have any magical effect, only when crops are lacking, or long-term comparisons can be seen. And the products that can see the effect very quickly usually contain conditioners. Many people also have a misunderstanding about regulators. There are two types. One is that regulator hormones are worthless, and the other is that regulator hormones are. Both of these perceptions are biased.
When the growth of crops is too weak, or when the growth is critical, it is still necessary to use regulators to promote growth, but if the nutrient supply is not in place, the crops will be "obesity". Symptoms & rdquo; growth deformities, or premature aging. Nutrition and regulation is a good match. In addition, long-term use of conditioners is not recommended for perennial crops (fruit trees), otherwise it is easy to shorten the tree age.