How to distinguish the quality of water-soluble fertilizer?

Water-soluble fertilizer is actually formula fertilizer, and different formulations are formulated according to different crops, different soils and different water quality, in order to meet the nutritional needs of crops to the maximum extent, improve fertilizer use efficiency and reduce waste, so, formula is the key to distinguish between good and bad water-soluble fertilizer.

Look at the ratio of nitrogen, phosphorus and potassium

For example, for the commonly used high potassium formula, according to the nutritional requirements of general crops during the fruit setting period, the best effect is achieved when the ratio of nitrogen, ∶, phosphorus, ∶ and potassium is controlled at 2 ∶ 1 ∶ 4, and there will be great differences in different ratios.

To see whether the trace elements are complete and whether the proportion is reasonable.

For a good water-soluble fertilizer, all six trace elements must be contained, and there must be a scientific ratio, because there is a problem of antagonism and coordination among the nutrient elements. Water-soluble fertilizer is not good if the content of one or more elements is high. but the proportion is scientific and reasonable.

Look at the content

Good water-soluble fertilizer uses industrial-grade or even food-grade raw materials, with high purity, and does not add any fillers, so the content is relatively high, and 100% are nutrients that can be absorbed and utilized by crops. the content of nitrogen, phosphorus and potassium can reach 60% or more. The content of poor water-soluble fertilizer is generally low, each less content, the cost will be different, the price of fertilizer will be different.

Look at water solubility

To identify the water solubility of water-soluble fertilizer, you only need to dissolve the fertilizer into clear water to see whether the solution is clear and transparent. If the color of the fertilizer is the same as that of clear water, the water solubility is very good; if the solution is turbid or even precipitated, the water solubility is very poor. Can not be used in the drip irrigation system, fertilizer waste will be more.

Smell it.

Good water-soluble fertilizers are made from high-purity raw materials with no taste or a very light fragrance. While odorous fertilizers are either added with hormones or too many harmful substances, this fertilizer works quickly, but water-soluble fertilizer has no benefit to the disease resistance and sustainable yield and quality of crops.

Make a comparison

After the preliminary screening of water-soluble fertilizer through the above simple methods, and then do field comparison, through the actual application effect to determine what kind of water-soluble fertilizer. Good fertilizer will not work very quickly, because nutrients have a process of absorption and transformation. When a good water-soluble fertilizer is used for two or three times, there will be obvious differences in plant growth, crop quality, crop yield and disease resistance. the more times it is used, the greater the difference.

Liquid water soluble fertilizer

According to industry standards, there are generally six kinds of liquid fertilizers in the current market: amino acids, humic acid, trace elements, medium elements, a large number of elements and organic water-soluble fertilizer. although the types are different, the quality is more or less the same. it mainly starts from the following aspects: one look, two names, three smells, four freezing, five tests.

1. Look at the physical state of the product. Good liquid fertilizer products are clear and transparent, clean and free of impurities, while black solutions such as suspended fertilizers such as amino acids and humic acid are opaque, but careful observation shows that there is no precipitation at the bottom of the bottle after the good products are inverted. There may be a lot of solid insoluble matter in the bottle of poor quality products.

2. Weigh the product weight. According to industry standards, each product has a minimum nutrient element content requirement. Each nutrient element in liquid fertilizer is measured in g hammer L, which means the mass of nutrient elements per unit volume. The greater the value, the heavier the liquid product of the same volume, the greater its proportion. Therefore, the specific gravity is an important index to measure the quality of liquid fertilizer products, good products do not necessarily have a large proportion, but the definite content of small proportion is not sufficient. The proportion of qualified amino acid, humic acid and organic water-soluble fertilizer is generally more than 1.25, that is, the weight of 1 liter of liquid fertilizer is more than 1.25 kg, and the proportion of large, medium and trace element liquid fertilizer is more than 1.35.

3. Smell the product three times. Good products have no obvious smell, and some products have a slight smell of ammonia under weak acid or weak alkaline conditions. There is a strong ammonia flavor is the pH did not master, there is a special flavor is generally to cover some smells, pungent smell is generally caused by the addition of substances that should not be added.

4. Freeze and test the stability of the product. Liquid fertilizer solution in the precipitation of solids, generally divided into two cases, one is long-standing slowly precipitation, the other is low temperature, solubility reduction precipitation, freezing is to test the stability of the product at low temperature, good products placed in the refrigerator for 24 hours will not be stratified crystallization, and those stratified crystallization products do not choose good raw materials, control the production process.

5. The fifth test is not to test the content of nutrient elements, but to test the nature of the product as far as possible. For example, using PH test paper to detect its acidity and alkalinity, manufacturers with high content of fluid fertilizer may show strong acid or strong alkali, which is not safe for crops, and it is very difficult to mix fluid fertilizer with other pesticides. The PH value of the products produced by skilled manufacturers is close to neutral or weak acid and weak alkaline. Use potassium dihydrogen phosphate or monoammonium phosphate solution to test whether "sugar alcohol" contains sugar alcohol, products containing sugar alcohol, calcium ion chelation degree is high, will not precipitate when encountered with phosphorus-containing solution, crops absorb and move quickly; check product safety with low dilution multiple, good liquid fertilizer products do not contain hormones, electrical conductivity is much lower than powder, it is safe even if dilution multiple is very low, it can be diluted 100 times, 50 times or even lower multiple spray.