As an all-purpose foliar fertilizer, potassium dihydrogen phosphate is very popular among people. Although the price is a bit high, the application effect of genuine potassium dihydrogen phosphate is indeed good.
Although potassium dihydrogen phosphate is very effective, it also has its own little partner. If used together, the effect will be better. In addition, there are also taboos of their own, which once violated will have no effect. Is the potassium dihydrogen phosphate that everyone knows limited to foliar spraying? Let’s take you through other ways to use it.
1. The main usage of potassium dihydrogen phosphate
(1) Soaking and mixing seeds
Wheat seeds will be mixed soon. Use about 200g of potassium dihydrogen phosphate per acre, add an appropriate amount of water, so that the solution is 7 cm above the seeds, soak the seeds for 10-20 hours, remove them and dry them before sowing. The soaked seeds can also be mixed with acidic pesticides for seed dressing.
If potassium dihydrogen phosphate is used for seed dressing, 50kg of seeds should be mixed with about 2.5 to 3 kg of water. Spray the seeds evenly with a sprayer and turn them in time. The sprayed seeds can be sown after 2 hours of simmering and drying. Treated seeds can promote early emergence of seedlings, increase the number of roots and branches, and make the plants grow robustly.
(2) Root irrigation
Use 1:5000 or 1:1500 potassium dihydrogen phosphate solution for root irrigation, which can be used as a quick-acting phosphorus and potassium fertilizer to coordinate the effective supply of nitrogen fertilizer and improve grain yield. Heavy, increase production.
(3) Foliar spray fertilizer
Cabot wheat, rice and other food crops should be sprayed once each during the greening stage, booting stage, early flowering stage and grain filling stage. About 200 g of potassium dihydrogen phosphate, mixed with 20-30 kg of water, and sprayed evenly on the stems and leaves of crops.
For peanuts, soybeans, sesame, etc., during the flowering, pod-setting and fruit-full stages, spray 50 grams of potassium dihydrogen phosphate mixed with 20 kilograms of water each time;
Fruit trees , vegetables, fruits, etc., during the flowering stage, young fruit stage, and fruit expansion stage, use 50 grams of potassium dihydrogen phosphate mixed with 20 kilograms of water and spray each time; it can promote plant metabolism, mature earlier, enhance photosynthesis and chlorophyll content, Promote grain plumpness, improve fruit sweetness, resist drought and high temperature, etc.
(4) Base fertilizer
Apply 8-12kg of potassium dihydrogen phosphate per 667 m2, combined with an appropriate amount of nitrogen fertilizer, and no longer apply phosphorus and potassium fertilizer. Potassium dihydrogen phosphate cannot be applied before soil preparation, but should be applied after soil preparation and before sowing.
2. The six best partners of potassium dihydrogen phosphate
1. Potassium dihydrogen phosphate + Urea quickly replenishes nutrients, enhances photosynthesis, promotes growth and increases yield.
Urea has a very strong ability to penetrate the leaf cell membrane, and its permeability coefficient is close to that of water. As a top dressing, urea should be the fastest absorbed fertilizer, and its fertilizer effect is also very fast. When 0.3% urea and 0.3% potassium dihydrogen phosphate are sprayed on the leaves, urea can promote faster and better absorption of potassium dihydrogen phosphate on the crop leaves, and the utilization rate of potassium dihydrogen phosphate is also greatly improved.
2. Potassium dihydrogen phosphate + paclobutrazol, promote flower bud differentiation
Apply flower bud differentiation period of fruit trees such as citrus (usually from November to January) to make citrus bloom. The flower buds differentiate better, promoting more flowers and fruits next spring.
3. Potassium dihydrogen phosphate + chlormequat, control growth
High concentration of dihydrogen phosphate Potassium has a certain effect in controlling growth and promoting the transformation of vegetative growth into reproductive growth, but the effect is not obvious. If the plant growth is severe, it is recommended to use chlormequat and potassium dihydrogen phosphate together to control the growth and shoot shoots better. Moreover, with the supplement of phosphorus and potassium, it is better for the original leaf photosynthesis and fruit growth of the crop. Effect.
4. Potassium dihydrogen phosphate + glucose, foliar spraying has better effect
Spraying 0.2% potassium dihydrogen phosphate plus 0.3% glucose solution on crops can increase the growth rate of crops. Due to the accumulation of crop dry matter, glucose can be directly absorbed by plants, and 0.2% urea solution can be added. In this way, potassium dihydrogen phosphate + glucose + urea is a complete nutrient solution needed by plants, and it also has a good preventive effect on crop gray mold and downy mildew.
5. Potassium dihydrogen phosphate + boron can improve fruit setting rate, seed setting rate, increase yield, and the effect is very outstanding
When used together with potassium dihydrogen phosphate + boron, the effect is doubled: promoting flower bud differentiation, preserving flowers and fruits, increasing pollination rate, enlarging color and sweetening, strong and full seed filling, resisting lodging and preventing premature aging, etc.
6. Potassium dihydrogen phosphate + brassinolide, good anti-freeze, cold and stress resistance
Brassinolide is a highly efficient plant hormone that can balance and regulate Plant growth promotes the ability of crops to absorb nutrients. Potassium dihydrogen phosphate, which contains phosphorus and potassium, can be absorbed by plants 30 minutes after spraying on the leaves. Three days before spraying potassium dihydrogen phosphate + sprucein lactone , it is best to apply fertilizer to the crops once, because after spraying potassium dihydrogen phosphate and brassinolide, the crops can absorb nutrients from the soil to the maximum extent.
The combination of potassium dihydrogen phosphate and brassinolide can greatly improve the cold resistance of crops. When fruit trees encounter late spring cold after blooming in spring, it will cause serious flower and fruit drop. Before the late spring cold comes, spraying 0.2% potassium dihydrogen phosphate + calypsin lactone can reduce the harm of late spring cold to fruit drop and flower drop, and maximize the plant’s cold resistance. Spraying 0.2% potassium dihydrogen phosphate + calypsin lactone before the cold wave in winter can increase the cold resistance of crops by 1-2°C.
3. 8 taboos on the use of potassium dihydrogen phosphate
1. It is prohibited to mix it with alkaline products
1% dihydrogen phosphate The pH of potassium aqueous solution is around 4.6.�, it is acidic, and chemical reactions will occur when mixed with alkaline fertilizers and pesticides. Abnormal chemical reactions such as flocculation, precipitation, discoloration, heat generation, and bubbles may occur. This will lead to the failure of the function of potassium dihydrogen phosphate.
The alkaline pesticides that cannot be mixed are Bordeaux mixture, lime sulfur mixture, copper hydroxide (can be killed), rosin mixture, sodium dipotassium tetrachloride, bensulfuron-methyl (weakly alkaline), Sodium pentachlorophenate, alkaline fertilizers that cannot be mixed are: ammonia, lime, plant ash, calcium magnesium phosphate fertilizer, ammonium bicarbonate, etc.
2. It is prohibited to mix with products containing carbonate
Because carbonate and hydrogen ions of potassium dihydrogen phosphate react to produce carbon dioxide (CO2) gas. Such as potassium carbonate, ammonium bicarbonate, ammonium bicarbonate, sodium bicarbonate, etc.
3. It is forbidden to mix with products containing copper ions
Potassium dihydrogen phosphate cannot be mixed with copper hydroxide, basic copper sulfate, calcium copper sulfate, cuprous oxide, and copper hydroxide , quinoline copper and other copper preparations are mixed, these free copper ions will react with phosphate ions to form flocculation and precipitation.
Potassium dihydrogen phosphate + kasugamycin king copper precipitation
4. Medium and trace amounts in the free state are prohibited Elements (calcium, magnesium, zinc, iron) are mixed, and the sugar alcohol form is ready for use.
These free metal ions will react with phosphate ions to form flocculation and precipitation, such as calcium, magnesium, zinc, iron , manganese products.
Sugar alcohols are easily decomposed when exposed to light or high temperatures, and trace elements become free ions, which may also produce flocculation. like precipitation. Stearic acid 1801 is recommended to be prepared and used immediately and not stored for a long time.
Inorganic salts are in free form, so they cannot be mixed with zinc sulfate, ferrous sulfate, manganese sulfate, copper sulfate, etc. Mix fertilizer products.
Pesticides such as mancozeb, mancozeb, vitriol, metalaxyl, mancozeb, etc. cannot be mixed! Mixing with mancozeb may cause precipitation and produce toxic gases.
The use of chelated EDTA will not react with potassium dihydrogen phosphate, because the chelated medium and trace elements It will complex these ions, making them more stable and will not produce free metal ions.
5. Excessive use in the early growth period is prohibited
Potassium will have an antagonistic effect with magnesium, calcium and other ions, affecting the absorption of these two types of ions, which is not conducive to the growth of plant cells and affects plant extraction. The longer the seedlings are, the greater the impact will be on later yields. Therefore, it is not recommended to use potassium dihydrogen phosphate during the seedling stage (1-3 leaves) and before the flowering stage of vegetables and beans to avoid damage to seedlings, flower and pod loss, and if used too early on soybeans, it will cause yield reduction.
6. It is forbidden to replace potassium dihydrogen phosphate as base fertilizer
Because potassium dihydrogen phosphate is very water-soluble Well, it dissolves easily when exposed to water. If it is buried deep in the soil, it is easily washed away by rainwater. The effect is short-lived, so it is not recommended to be used as a base fertilizer. It is better to use compound fertilizer as a base fertilizer, which is slow-release and long-lasting. Potassium dihydrogen phosphate has good water solubility and strong quick-acting effect. It can be used for leaf spraying and root flushing during critical periods such as flower bud differentiation.
7. It is prohibited to use it at high temperatures and at high concentrations
High temperatures will cause the concentration of potassium dihydrogen phosphate solution to increase, which can easily cause fertilizer damage. If the concentration is too high, it will also cause fertilizer damage such as burning leaves and roots. The spraying time of potassium dihydrogen phosphate should avoid the high temperature period at noon. It is best to use it before 10 a.m. or after 4 p.m. It is prohibited to use high-concentration foliar sprays during high-temperature seasons.
Gramine crops such as wheat and rice can be sprayed at 300-500 times. For other crops, it is recommended to spray at 500-800 times. Concentrated spraying is preferred, and the dilution factor should be no less than 300 times, preferably more than 500 times.
8. It is forbidden to add EC first and then potassium dihydrogen phosphate
When mixed with EC pesticides, add EC last to avoid affecting the dissolution of potassium dihydrogen phosphate. Because the emulsifiable concentrate was put in first, and then the potassium dihydrogen phosphate was added without secondary dilution, the oil coated the potassium dihydrogen phosphate particles. Therefore, when dispensing, be sure to dissolve the powder and granules first, and finally add the emulsifiable concentrate.
