When applying fertilizer through drip irrigation, first drip clear water. Wait until the pipes are filled with water before starting to fertilize. Immediately after fertilization, drip clean water for 20 to 30 minutes to completely drain the remaining fertilizer solution in the pipeline (a conductivity meter can be used to monitor whether it is completely drained). If the tubes are not washed, moss, algae and other lower plants or microorganisms may grow at the drippers, clogging them.

Long-term use of drip irrigation and fertilization in greenhouses or greenhouses can lead to the accumulation of salt on the surface, affecting root growth. Sub-film drip irrigation can be adopted to inhibit the migration of salts to the surface layer.

Pay attention to the uniformity of fertilization. In principle, the slower the fertilization for drip irrigation, the better. Especially for elements with poor mobility in the soil (such as phosphorus), extending the fertilization time can greatly improve the utilization rate of difficult-to-move nutrients. When applying drip irrigation fertilizer during the dry season, it is recommended to complete the fertilization within 2 to 3 hours. Under the condition that the soil is not short of water and on the premise of ensuring uniformity, the sooner the better.

To avoid excessive irrigation, it is generally sufficient to keep the root layer moist. The depth of the root layer varies greatly depending on different crops. You can use a shovel to dig up the soil at any time to understand the specific depth of the root layer. Excessive irrigation not only wastes water, but more seriously, nutrients are washed away below the root layer, resulting in the waste of fertilizers and reduced crop yields. In particular, urea and nitrate nitrogen fertilizers (such as potassium nitrate, calcium ammonium nitrate, nitrophosphate fertilizers and water-soluble fertilizers containing nitrate nitrogen) are extremely prone to being lost with water.

It is important to understand the hardness and pH of the irrigation water to prevent sedimentation and reduce fertilizer efficiency. Especially in areas with saline-alkali soil, the precipitation of calcium phosphate salts is very common and is one of the reasons for clogging the drippers. Meanwhile, phosphate precipitation is also an important reason for reducing the effectiveness of phosphate fertilizer.

When applied in combination with other fertilizers, water-soluble fertilizers are usually only used as top dressings. When recommending fertilization, base fertilizer and top dressing should be combined, organic fertilizer and inorganic fertilizer should be combined, and water-soluble fertilizer and conventional fertilizer should be combined. Do not emphasize that water-soluble fertilizers can replace other fertilizers. They should be used in combination to reduce costs and give full play to the advantages of various fertilizers.

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