1. Outer packaging identification method. The compound fertilizer packaging bag must be marked with the product name, nutrient content (grade), trademark, net weight, standard code, factory name and address, production license number and registration certificate number, etc. If the above signs are missing or incomplete, the packaging will be rough. It may be fake and inferior compound fertilizer.

Special attention should be paid to compound fertilizers with obvious signs of folding and sealing on the packaging bag seal, as this phenomenon may lead to adulteration. In addition, there should be a certificate of quality when opening the package, and pay attention to the production date. The longer the compound fertilizer is stored, the total nutrients will decrease. ?

2. Simple visual inspection method. Generally speaking, as long as it is genuine, compound fertilizer must go through a complex process, including extrusion granulation, disc granulation, roller granulation or tower granulation, etc. The color is simple, either off-white or light gray, which is very difficult to find. There is little variegation, and the granulation is relatively uniform, round or cylindrical.

Most of the fake and inferior special-purpose compound fertilizers have not been deeply processed and are crudely made or generally mixed. They are impure in color and unevenly granulated. Some are not even granulated and become flour-like. ?

3. Hand pinch feeling method. Real compound fertilizers are generally made by melting, cooling, granulating at high temperatures and then drying. They have good stability, high hardness, and consistent hardness. They are not easily broken or softened when pinched by hand. Fake and inferior compound fertilizers have poor hardness and are inconsistent in hardness. They can easily form lumps or become muddy when pinched by hand. ?

4. Smell and taste method. Pinch a handful of compound fertilizer and smell it. If you find an ammonia smell, it is a low-content compound fertilizer with ammonium bicarbonate mixed in, and the total content is low.

If you find other peculiar smells, it is mostly fake and inferior compound fertilizer. True compound fertilizers, or those with a total nutrient content of more than 25%, generally have the advantages of stable ingredients and will not decompose or melt, so they will not have any peculiar smell and generally will not have an ammonia smell. ?

5. Dissolution method. Put the compound fertilizer particles in a small amount of water. After a period of time, you can judge based on the dissolution situation. The compound fertilizer particles will disperse and dissolve. After shaking, the solution will be stable with almost no residue. Fake and inferior compound fertilizers have poor solubility or do not dissolve at all. ?

6. Fire method. Heating or burning the compound fertilizer particles, the quality of the fertilizer can be identified based on the melting state, smoke, smoke smell and residue. After heating, the compound fertilizer will bubble, melt (the more nitrogen, the faster it melts), smoke, and emit an ammonia smell. The particles will deform and become smaller. The higher the concentration, the less residue will be left.

High-quality, high-concentration compound fertilizer burns very completely with almost no residue. On the contrary, those that cannot burn or burn but have no ammonia smell are likely to be fake compound fertilizers.

Extended information:

Compound fertilizer refers to chemical fertilizers containing two or more nutrient elements. Compound fertilizer has the advantages of high nutrient content, few side components and good physical properties. It plays a very important role in balancing fertilization, improving fertilizer utilization efficiency, and promoting high and stable crop yields.

But it also has some disadvantages, such as its nutrient ratio is always fixed, while the types, quantities and ratios of nutrient elements required by different soils and different crops are diverse. Therefore, it is best to conduct a soil test before use to understand the texture and nutritional status of the soil in the field. In addition, attention should be paid to applying it in conjunction with unit fertilizers to achieve better results.

Reference: Baidu Encyclopedia_Compound Fertilizer