First, look at the packaging.

The product name, nutrient content, trademark, net weight, standard code, factory name, address, production license number and fertilizer registration certificate number must be marked on the packaging bag of commercial fertilizer. If the above signs are missing or incomplete, it may be fake fertilizer.

Second, the smell

Judging from the special smell of fertilizer alone. For example, ammonium bicarbonate has a strong ammonia smell; Ammonium sulfate is slightly acidic; Calcium superphosphate has sour taste, and the smell of fake and inferior products is not obvious; However, when waste sulfuric acid is used in the production of superphosphate, it will produce a strong pungent and strange sour taste. This kind of fertilizer is very toxic and easily damages or burns crops.

Third, look at the seal.

Pay special attention to the fertilizer with obvious signs of unpacking on the seal of the packaging bag, which may be adulterated.

Fourth, look at the appearance.

Nitrogen fertilizer (except lime nitrogen) and potassium fertilizer are mostly crystals. Phosphate fertilizer is mostly block or powder amorphous, calcium magnesium phosphate is powder and calcium superphosphate is mostly porous block. Compound fertilizer particles are relatively uniform, the surface is smooth, and it is not easy to absorb moisture and agglomerate. Compound fertilizer with uneven particle size, roughness, high humidity and easy caking can basically be judged as false.

Fifth, look at the color.

Different fertilizers have their own unique colors. Nitrogen fertilizer is almost white except lime nitrogen, and some are slightly yellowish brown or light blue (except for other components). Potassium fertilizer is white or reddish, such as potassium dihydrogen phosphate is white; Phosphate fertilizers are mostly dark gray, such as calcium superphosphate, calcium magnesium phosphate, and diammonium phosphate. And farmers can make a general distinction according to this.

6. Combustion: the chemical fertilizer sample is heated or burned, and the chemical fertilizer is identified from the aspects of flame color, melting, smoke smell and residue.

Nitrogen fertilizer and ammonium bicarbonate are directly decomposed to produce a large amount of white smoke, which has a strong ammonia smell and no residue; Ammonium chloride, directly decomposed or sublimated, produces a lot of white smoke, which has a strong ammonia taste and sour taste, and has no residue; Urea can melt quickly, emit white smoke and burn in charcoal fire, or when the glass sheet contacts white smoke, you can see a layer of white crystals attached to the glass sheet; Ammonium nitrate does not burn but melts and boils, giving off smoke with ammonia smell.

Calcium superphosphate, calcium magnesium phosphate and phosphate rock powder have no effect on red carbon; Bone meal soon turned black and gave off a burnt smell.

Potassium fertilizer, such as potassium sulfate, potassium chloride, potassium magnesium sulfate, etc. Don't change on the red charcoal and make a crackling sound.

The combustion of compound fertilizer is closely related to its raw materials. When there is ammonia nitrogen or amide nitrogen in its raw materials, it will give off a strong ammonia smell and have a lot of residues.

Seven, soluble in water

Dissolution: Dissolve fertilizer in water. Take 1g fertilizer, put it in a clean glass tube and other utensils, add 10mg distilled water (or clean cold boiled water), shake well and see if it dissolves. Nitrogen fertilizer and potassium fertilizer are dissolved, and if they are turbid, they are fake and inferior fertilizers; Calcium superphosphate is soluble in water and has residue; Calcium superphosphate is soluble in water, with no or little residue; Ammonium bicarbonate is soluble in water, but it has a strong ammonia smell; Lime nitrogen is insoluble in water and smells like bubbles and calcium carbide and chlorine.

It should be noted that although some fertilizers are real, the effective nutrient content is not up to standard or very low. In this case, you should complain to the local fertilizer department, collect or keep some samples, and buy fertilizer invoices and other related bills to provide necessary evidence for safeguarding your legitimate rights and interests.

Chemical fertilizer is called chemical fertilizer for short. Fertilizers made by chemical and/or physical methods contain one or more nutrient elements needed for crop growth. Also known as inorganic fertilizer, it includes nitrogen fertilizer, phosphorus fertilizer, potassium fertilizer, micro-fertilizer and compound fertilizer.

They have the following characteristics: simple ingredients and high nutritional content; Fast fertilizer efficiency and fierce fertility; Some fertilizers have acid-base reaction; Generally, it does not contain organic matter and has no effect on improving soil and fertility. There are many kinds of chemical fertilizers, and their properties and application methods are quite different.

Chemical fertilizer containing one or more nutrient elements needed for crop growth. Short for chemical fertilizer. Fertilizers containing only one indicated content of nutrient elements are called unit fertilizers, such as nitrogen fertilizer, phosphorus fertilizer, potassium fertilizer, trace macro-element fertilizer and trace element fertilizer.

A chemical fertilizer containing two or three of the three nutrient elements of nitrogen, phosphorus and potassium, and its content can be marked, is called compound fertilizer or mixed fertilizer. The solubility of effective components of chemical fertilizer in water is usually the standard to measure the effectiveness of chemical fertilizer. Grade is the main index of fertilizer quality, which refers to the percentage of effective nutrient elements such as nitrogen, phosphorus, potassium, calcium, sodium, manganese, sulfur, boron, copper, iron, molybdenum and zinc or their oxides in fertilizer products.

Phosphate fertilizer, nitrogen fertilizer and potassium fertilizer are fertilizers that are in great demand for plants.

Extended data:

Nitrogen, phosphorus, potassium and other nutrients in the soil can not meet the needs of crop growth, and need to be supplemented by applying fertilizers containing nitrogen, phosphorus and potassium. In addition to chlorine, other trace elements need to be combined with micro-fertilizer application. Generally, fertilizers are mostly inorganic compounds, and only urea CO(NH2)2 is an organic compound.

Any chemical fertilizer containing only one nutrient element and marked content is called unit fertilizer, such as nitrogen fertilizer, phosphorus fertilizer and potassium fertilizer. Any chemical fertilizer that contains two or more of the three nutrient elements of nitrogen, phosphorus and potassium and can indicate its content is called compound fertilizer or mixed fertilizer. Grade is the main index of fertilizer quality. Refers to the percentage of effective nutrient elements or their oxides in chemical fertilizer products.

According to chemical properties, chemical fertilizers can be divided into:

1. Physiological acid fertilizer. In the aqueous solution of chemical fertilizer, pasture absorbs too many chemical fertilizer cations, and the remaining anions generate corresponding acids, which makes the solution sour. Most ammonium salts and potassium salts belong to this fertilizer.

2. Physiological alkaline fertilizer. If the grass absorbs and utilizes anions faster than cations, excessive cations will appear in the soil solution, resulting in corresponding alkaline compounds, making the solution alkaline, such as calcium nitrate and magnesium nitrate.

3. Physiologically neutral fertilizer. Grass absorbs anions and cations at roughly the same speed, and the soil solution reaction is neutral, such as potassium nitrate, ammonium nitrate and urea. According to the composition of nutrients, chemical fertilizers can be divided into: nitrogen fertilizer, phosphorus fertilizer, potassium fertilizer, compound fertilizer, trace elements and so on. Fertilizer can be divided into base fertilizer and topdressing according to its use.

In addition, chemical fertilizers can also be divided into quick-acting fertilizers, slow-acting fertilizers and long-acting fertilizers. Soil fertilizer, foliar fertilizer, etc.

References:

Baidu encyclopedia: fertilizer