In China, the common solid water-soluble fertilizer of elemental fertilizer, compound fertilizer and organic models fertilizers. Wherein elemental fertilizer include: urea, ammonium sulfate, ammonium nitrate, calcium, potassium dihydrogen phosphate, potassium chloride, potassium nitrate, diammonium industrial grade ammonium, water-soluble potassium persulfate; compound fertilizer comprising: a water-soluble NPK compound fertilizer (China called "a large number of elements in the water-soluble fertilizer); the organic models fertilizers including: added amino acids, humic acid, alginic acid NPK fertilizer.

Water-soluble fertilizer should be large-scale development of low-cost

Currently, solid water-soluble fertilizer in China there are some problems. First, too much emphasis on water insoluble matter, and not allow the amount of slag is determined depending on the irrigation mode. Second, the excessive packaging increases the cost. Third, the price is too high, can afford only cash crops. Fourth, the standard is too high, limiting the development of the low concentration of water-soluble fertilizer products. Fifth, there is no transport concessions and tax breaks.

Based on these problems, it should be able to find a positive solution. From the current situation, the large-scale development of low-cost water-soluble fertilizer. Compound fertilizer production equipment and preferential terms, the development of water-soluble fertilizer or BB fertilizer. Such as water-soluble compound fertilizer tower granulation or extrusion granulation water-soluble BB fertilizer.

Liquid fertilizer quality needs to be improved

The second largest category of water-soluble fertilizer liquid fertilizer. Nutritional element as a solute dissolved in the water solution (supernatant liquid fertilizer), or by means of suspending agents become suspended in water and the suspension (suspension fertilizers).

Of liquid fertilizer of the main problems are: First, instead of conventional fertilizer liquid fertilizer rarely; second, there is still the problem of excessive packaging; Third, is not conducive to the long-distance transport; fourth, the network channel is too complex, layers of wholesale layers increases, resulting in the terminal price is too high; Fifth, the quality of instability, exist to varying degrees sedimentation, stratification, agglomeration, lack of nutrients. Sixth, the "prime" (urea, pigments, hormones).

Rational application of water-soluble fertilizer requirements

First, follow the principle of a few times. The principle of the plant roots to absorb nutrients uninterrupted characteristics to reduce leaching losses caused by a large number of one-time fertilization. Per acre amount of water-soluble fertilizer at 2-6 kg / mu.

Second, follow the principle of balance of nutrients. Especially in fertigation, root growth-intensive, large, then reduce soil nutrient supply dependency, more dependent on the nutrients provided by drip irrigation. Have higher expectations of reasonable proportion and concentration of nutrients.

Prevent fertilizer burn leaves and roots, especially sprinkler and micro-irrigation, fertilization, and prone to the phenomenon of burning leaves. Greenhouses or greenhouse fertigation for a long time, will cause surface salt accumulation, affecting root growth. The drip irrigation suppression salt can be used to migrate to the surface.

Fourth, to avoid excessive irrigation, generally 20-40 cm soil depth can be kept moist. Excessive irrigation is not only a waste of water, serious nutrient leaching below the root layer, a waste of fertilizer, crop production. Especially water-soluble fertilizer urea, nitrate fertilizer (such as potassium nitrate, water-soluble fertilizer) very easily with water loss. To learn the the irrigation water hardness and pH, to avoid the precipitation, reduce fertilizer. Especially for the saline-alkali soil and limestone, calcium phosphate precipitation is very common and is an important cause of lower fertilizer. Therefore, before fertilization recommendations do first test is to determine the dilution factor and the pH of the solution

Fifth, completely water-soluble fertilizer is usually only top-dressing. Stresses the basal and top dressing, the combination of organic and inorganic, water-soluble fertilizer combined with conventional fertilizer. Do not stress water-soluble fertilizer instead of fertilizer, to be used in conjunction with, and reduce costs.