1. Compound fertilizer should not be used for seedling fertilizer and middle and late fertilizer.

The compound fertilizer has a long effect and should be used as a base fertilizer. The compound fertilizer processed and granulated is slower than the powdered fertilizer, is not easy to be lost and volatilized, and has a long duration of fertilizer effect. It is easy to use as a base fertilizer, and the general dosage is 30-40 kg. Compound fertilizer should not be used for seedling fertilizer and mid-late fertilizer, so as to avoid crop steepness and steepness.

2, pay attention to the use of nutrients.

Different brands and different concentrations of compound fertilizers use different raw materials, and the production should be selected according to soil type and crop type. Nitrate-containing compound fertilizer should not be used in leafy vegetables and paddy fields; compound fertilizer containing ammonium ions should not be applied on saline-alkali soil; compound fertilizer containing potassium chloride or chloride ion should not be used on chlorine-free crops or saline-alkali soil; Compound fertilizer containing potassium sulfate should not be used in paddy fields and acidic soils. Otherwise, it will reduce fertilizer efficiency and even poison crops.

3. Pay attention to the use with elemental nitrogen fertilizer.

Crops require less nitrogen fertilizer during seedling stage. Therefore, crops with compound fertilizer as base fertilizer should be supplemented with quick-acting nitrogen fertilizer in time for topdressing according to the fertilizer requirements of different crops to meet crop nutrient requirements.

4, pay attention to avoid direct contact with seeds or fertilizers.

The compound fertilizer has a high nutrient content. If it is in direct contact with the seed or seedling roots, it will affect the emergence of seedlings and even the burning of seedlings and rotten roots. When planting, the seeds should be separated from the point application and the compound fertilizer by 5-10 cm. It should not be directly applied to the same point with the seeds, causing fat damage.

5. Pay attention to choosing the right concentration.

Most compound fertilizers are formulated according to the average nutrient status of soil types in a certain area and the ratio of fertilizer required for large crops. There are high, medium and low concentration series of compound fertilizers on the market. Generally, the total concentration of total nutrients is between 25% and 30%, the medium concentration is between 30% and 40%, and the high concentration is above 40%. It is necessary to use economical and efficient compound fertilizers depending on the region, soil and crops. Generally, high-concentration compound fertilizer is used in economic crops, which can make crops excellent in quality, less fertilizer residues, and high utilization rate.

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