Detailed Explanation of the Characteristics and Functions of Common Fertilizers
In sandy soil, all phosphate fertilizer should be applied as a base fertilizer, half of the nitrogen fertilizer should be applied as a base fertilizer, and the other half should be applied as a top dressing in stages during the growth and development process. Then, the amount of irrigation water should not be too large, to avoid fertilizer loss caused by flood irrigation. In clayey soil, where irrigation conditions are available, phosphate fertilizer and 2/3 of the nitrogen fertilizer can be applied as a base fertilizer, and 1/3 of the nitrogen fertilizer can be applied as a top dressing in stages. Where there are no...
Compound fertilizers have complete nutrients and can be divided into binary and ternary types; most have good physical properties, making them convenient to transport and store. The combination of the three elements is diverse, and flexible use is key; formulated fertilizers have been promoted recently, and multi-element types have already been developed.
(1) Monoammonium phosphate
Monoammonium phosphate is acidic, with 42% phosphorus and 11% nitrogen. Most of China's soils tend to be alkaline, so it is suitable to mix urea with monoammonium phosphate.
Nitrogen and phosphorus complement each other to increase fertilizer efficiency, saving labor, saving money, and increasing yield. To help farmers benefit more, use it to produce formulated fertilizer.
(2) Diammonium phosphate
Diammonium phosphate is somewhat alkaline, with 46% phosphorus and 18% nitrogen. Domestic diammonium phosphate has a lower content, with 45% phosphorus and 13% nitrogen.
In principle, it should be applied to acidic soil; for alkaline soil, monoammonium phosphate is better. It is best to mix it with urea when applying, and mix and use it immediately to increase yield.
(3) Ammonium phosphate
Monoammonium phosphate and diammonium phosphate combine into ammonium phosphate, with 46% phosphorus and 15% nitrogen. The granules are grayish-white and neutral, and it can also release nitrogen when encountering alkali.
It adapts to various types of soil and can be used as a base fertilizer and top dressing. The most suitable crops include wheat and rice, as well as soybeans and corn.
(4) Liquid ammonium phosphate
In producing liquid ammonium phosphate, the process is simple and the cost is low. It contains 7% nitrogen and 20% phosphorus, is easily soluble in water, and is somewhat acidic.
Its suspension performance is relatively good, it does not corrode and does not settle. It has broad adaptability and prospects, and nitrogen still needs to be added when applying it.
(5) Ammonium metaphosphate
Ammonium metaphosphate is neutral, and its property changes to weakly acid-soluble. In principle, it should be applied to acidic fields to promote its hydrolysis into monoammonium phosphate.
With 75% phosphorus and 16% nitrogen, physiologically acidic fertilizer should be chosen when adding nitrogen. The granules are grayish-white and do not cake, making storage and transportation convenient.
(6) Nitrophosphate fertilizer
Nitrophosphate fertilizer is somewhat acidic, and its compound components include phosphorus and nitrogen. With 26% nitrogen and 13% phosphorus, it is most suitable for medium wheat fields.
Because it contains nitrate nitrogen, it is best applied to dry fields. It can also release ammonia when encountering alkali, so storage and transportation must be strictly managed.
(7) Ammoniated superphosphate
After superphosphate is ammoniated, its physical and chemical properties change greatly. Most of the free acid is neutralized, making application, storage, and transportation convenient.
It can dissolve in water and become neutral, with an added ammonia content of 3%. Never mix it with alkaline substances; soybeans and green manure crops like it most.
(8) Ammonium sulfate
Ammonium sulfate is acidic, with 20% phosphorus and 16% ammonia. It is easily soluble in water and has a quick fertilizer effect, containing ammonium sulfate and ammonium phosphate.
Most of China's soils tend to be alkaline, and the application benefit is very obvious. It is suitable for various crops, and nitrogen should be increased when used for wheat.
(9) Potassium dihydrogen phosphate
Compound fertilizer potassium dihydrogen phosphate is suitable for foliar spraying. Use more than 100 grams per mu, and it promotes earlier maturity and larger grains.
It contains 52% phosphorus and also contains 34% potassium; it is easily soluble in water and weakly acidic, and can also be used for seed soaking and seed dressing.
(10) Calcium-magnesium-phosphorus-potassium fertilizer
Calcium-magnesium-phosphorus-potassium is a new fertilizer type, a gray powder that is alkaline. It contains 2% potassium and 17% phosphorus, and also contains calcium, magnesium, and other multiple nutrients.
It is insoluble in water and soluble in weak acid, and is suitable for acidic fields lacking calcium. Before use, it is best to compost it to improve fertilizer efficiency and obtain high yields.
(11) Potassium metaphosphate
Imitating potassium phosphate compound fertilizer, it is weakly acidic gray granules. Its phosphorus content is as high as 59%, and its potassium content reaches 37%.
It can dissolve in weak acid and slightly dissolve in water, and is most suitable for application in acidic soil. Because its nutrients lack nitrogen, nitrogen fertilizer needs to be mixed in when applying.
(12) Potassium nitrate
Potassium nitrate is called saltpeter, a white crystal with good properties. If mixed with carbon and sulfur, it can make gunpowder and is flammable and explosive.
It is easily soluble in water and neutral, and can be used for seed soaking and seed dressing. With 44% potassium and 13% nitrogen, foliar top dressing can increase yield.
(13) Nitrogen-potassium mixed fertilizer
Ammonium sulfate mixed with potassium sulfate is produced by the ammonia-soda process, with 16% potassium and 14% ammonia. It is easily soluble in water and physiologically acidic.
It adapts to various types of soil; during storage, transportation, and application, do not let it encounter alkali. Because its nutrients lack phosphorus, increasing phosphate fertilizer is key.
(14) Ammonium phosphate potassium
The ternary compound fertilizer ammonium phosphate potassium is a combination of ammonium phosphate and potassium sulfate; ammonium sulfate may also be added, and products can be divided into No. 1, No. 2, and No. 3;
No. 1 has 12% nitrogen and 12% potassium, and its phosphorus content can reach 24%. No. 2 has 10% nitrogen and 15% potassium, and its phosphorus content can reach 20%.
No. 3 has 10% nitrogen and 10% potassium, and its phosphorus content is as high as exactly 30%. According to the fertilizer requirements of crops, it is mostly used for fruit trees and high-value economic fields.
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Adding potassium to nitrophosphate can produce four types of nitric phosphate potassium; the first is frozen nitric phosphate potassium, with the contents of the three elements not much different;
It contains 15% nitrogen, 16% phosphorus, and also 17% potassium oxide. The second is carbonate nitric phosphate potassium, with 15% nitrogen and 18% potassium;
Its phosphorus content has 9% citrate-soluble phosphorus, and it is very suitable for acidic soil; carbon dioxide replaces sulfuric acid, lowering costs and making it cheap.
The third is phosphate nitric phosphate potassium, with three 17s, giving a strong fertilizer effect. All three of the above contain chlorine, so never use them on tobacco, sugarcane, or potatoes.
The fourth is chlorine-free nitric phosphate potassium, with potassium sulfate replacing potassium chloride; because production costs are high, it is only used for economic crops.
(16) Urea-potassium-phosphorus fertilizer
Urea, potassium, and phosphorus are blended into a ternary fertilizer, with complete nitrogen, phosphorus, and potassium nutrients; production uses potassium nitrate, melting and combining urea and diammonium phosphate.
It contains 14% phosphorus and 14% potassium, and also 28% nitrogen; nitrate nitrogen is 4%, ammonium nitrogen is 6%, and another 18% is amide nitrogen.
Because all three forms of nitrogen are present, it is heavily used on fruit trees and economic fields; and because the nitrogen-to-phosphorus ratio is 2 to 1, it is even more suitable for medium wheat fields.
Mineral fertilizers
Mineral fertilizers have been applied since early times, commonly lime and gypsum. There are also brine and agricultural salt, and ferrous sulfate is called black alum.
They are mainly used to regulate soil and improve soil physical and chemical properties. They benefit the reproduction of microorganisms and can supply nutrients both directly and indirectly.
(1) Lime
Lime can be divided into quicklime and slaked lime, and is suitable for improving acidic soil. In the south, there are podzolic red and yellow soils, and in the northeast, acidic white pulpy soils.
Its application can not only increase calcium, but also reduce diseases and insect pests. Apply 100 kg per mu, and do not mix it with ordinary calcium superphosphate, human urine, or manure.
(2) Gypsum
Gypsum is acidic in nature and is used to improve alkaline soil. Whether phosphate rock, raw gypsum, or calcined gypsum, all contain the two elements calcium and sulfur.
For dry land, apply 50,000 grams per mu, with deep plowing and fine fertilization to help improve the soil. For paddy fields, 3 kg per mu is needed, mainly used for dipping rice seedling roots.
(3) Brine
Brine has relatively complete nutrients, including potassium, sodium, calcium, magnesium, and nitrogen. The dark brown liquid is heavier than water, and is suitable for sandy loam and paddy fields.
Apply 50 kg per mu, and various crops all increase yield. Brine paste is dark brown and crystalline, easily soluble in water and strongly alkaline.
(4) Agricultural salt
Agricultural salt's component is sodium chloride, and it also contains boron, iodine, sulfur, magnesium, and potassium. It is a white crystal and neutral, and sodium replaces magnesium and potassium for crop use.
Rice, wheat, and soybeans all like sodium, as do sugar beets and flax. Only 5 kg per mu is needed, and mixing it with human urine gives a strong fertilizer effect.
(5) Maifan stone
Maifan stone has complete nutrients, and in ancient times people used it in medicine for health care; it is recorded in the Compendium of Materia Medica, and the authentic place of origin is Songshan.
Recently it has mostly been used as feed, and when used as fertilizer it can increase yield; adding sulfuric acid before fertilization can solve the difficulty of crop absorption.