What is fertilizer and common misunderstandings about npk compound fertilizer.

What is NPK compound fertilizer?

• Compound fertilizer refers to chemical fertilizers containing more than two main nutrients. It is the general term for compound fertilizers and mixed fertilizers. Compound fertilizers generally refer to chemical synthesis. For example, ammonium phosphate contains nitrogen and phosphorus; potassium nitrate contains nitrogen and potassium. Potassium dihydrogen phosphate contains phosphorus and potassium, and the ratio of nutrients is determined by the chemical structure.
• Another kind of mixed fertilizer generally refers to physical (mechanical) mixing, such as mixing ready-made solid nitrogen fertilizer, phosphate fertilizer, and potassium fertilizer, such as pellet method and blending method (BB fertilizer). The ratio of nutrients can be adjusted as needed. Optional.
• Due to different goals of nutrient ratio, this type of fertilizer is divided into general-purpose fertilizer and special-purpose fertilizer. The former, such as 15-15-15, can be used directly or as raw material, while the latter, such as rice-specific fertilizer, has a nutrient ratio specifically suitable for rice. .
• Due to the development of compound fertilizer production technology, liquid raw materials such as phosphoric acid and sulfuric acid are often used to participate in the production and mixing process of solid fertilizers, which also produces some chemical reactions. This makes it difficult to strictly distinguish between compound and mixed fertilizers. They can be collectively referred to as compound fertilizers.

What are some common misunderstandings about compound fertilizers?

The misunderstanding about the “all-roundness” of compound fertilizers

● Compound fertilizers are only richer in fertilizer element ratio than simple fertilizers, but the principle of scientific fertilization is to make more rational use of limited resources, so compound fertilizers are generally applied in conjunction with simple fertilizers so that they can be better absorbed and utilized by crops. For example, nitrogen fertilizers are highly mobile, while P and K fertilizers are less mobile, but the aftereffects of phosphorus and potassium fertilizers are long. Then, for crops with a relatively long growth period, we need to add some nitrogen fertilizer to maintain the nutrients needed by the crops.

Fertilizer is Perfect“Universal” misunderstanding

The so-called “universal” compound fertilizer refers to a compound fertilizer that has the same content of N, P, and K and is suitable for all crops, such as 15-15-15. However, whether in terms of actual operation or theory, this kind of fertilizer should not be promoted the most, and its sales have always been very good, mainly because of its success in sales.

Misunderstanding of fertilizer soil testing formula

• Factors affecting crop growth include: environment, soil, intercropping rotation, fertilization habits, as well as the growth cycle of the crop itself and its ability to absorb nutrients at different stages. Soil testing is only one part of the solution.
• But soil testing is currently the easiest method to do, so the soil testing formula is the most effective method at this stage.
• It can be said that formula fertilizer is the most scientific and reasonable compound fertilizer in the world.

The contradiction between quick effect and slow effect compound fertilizer

In the compound fertilizer family, quick-acting and slow-acting fertilizers exist as a contradiction. Whether it is quick-acting or slow-acting is only related to the crop itself. From the perspective of compound fertilizer alone, whether it is quick-acting or slow-acting does not prove the quality of compound fertilizer.

What are the disadvantages of compound fertilizers？

• The nutrient ratio is fixed and it is difficult to adapt to the different needs of various soils and crops. It is often necessary to supplement and adjust with simple fertilizers.
• It is difficult to meet the requirements of fertilization technology. The movement patterns of various nutrients in the soil and the requirements for fertilization technology are different. For example, nitrogen fertilizer has high mobility, P and K fertilizer have small mobility, but the aftereffect of phosphorus and potassium fertilizer is long.
• In terms of application, nitrogen fertilizers are usually used as top dressing, phosphorus and potassium fertilizers are usually used as base fertilizers and seed fertilizers, and compound fertilizers apply various nutrients at the same location and at the same time. In this way, it is difficult to meet the nutrient requirements of crops in a certain period.
• Therefore, it is necessary to understand the soil conditions in various places, the growth characteristics and fertilizer requirements of various crops, and apply appropriate compound fertilizers.

What are some common types of compound fertilizer?

Compound fertilizers can be divided into three categories according to their manufacturing processes: chemical compound fertilizers, formulated compound fertilizers and mixed compound fertilizers.

1. Chemical compound fertilizers are compound fertilizers made through chemical methods, such as potassium dihydrogen phosphate.
2. Formulated compound fertilizer is a compound fertilizer containing multiple elements that is re-granulated from two or more elemental fertilizers through a certain processing technology at a fertilizer manufacturer. Partial chemical reactions occur during the processing. What is commonly referred to as compound fertilizer is compound fertilizer. Mixed fertilizer mostly refers to this kind of compound fertilizer.
3. Mixed compound fertilizer is a compound fertilizer made by mechanically mixing several fertilizers. During the processing, it is simply mechanically mixed without chemical reaction. For example, ammonium chloride and ammonium phosphate are mixed together.

So overall, the nutrient range of compound fertilizers: Generally, the total content is in the range of 25% to 60%. Those with a total content of 25% to 30% are low-concentration compound fertilizers, those with a total content of 30% to 40% are medium-concentration compound fertilizers, and those with a total content of 25% to 30% are medium-concentration compound fertilizers. More than 40% is high-concentration compound fertilizer.

Conclusion

This article introduces some common misconceptions about compound fertilizers. First of all, compound fertilizers are not omnipotent. No compound fertilizer is omnipotent. As long as it is a compound fertilizer, it will have a certain degree of side effects. But on the other hand, compound fertilizers are not all harmful. The nitrogen in compound fertilizers can help plants grow roots, phosphorus can help plants’ stems become stronger, and potassium can make plants’ leaves fuller. So the specific fertilization depends on the composition of the soil. .