Humic acid fertilizer for correcting lemon yellowing and preparation method

The invention provides a humic acid fertilizer for correcting lemon yellowing and a preparation method. The 100% sum of the humic acid fertilizer for correcting the lemon yellowing consists of 25-38% of active humic acid, 10-15% of magnesium nitrate, 7-12% of citric acid, 8-11% of sodium tetraborate, 8-13% of urea, 2-8% of water-soluble monoammonium phosphate, 4-12% of potassium sulfate, 2-7% of zinc sulfate monohydrate and 1- 6% of ferrous sulfate. The magnesium nitrate, the citric acid, the sodium tetraborate, the zinc sulfate monohydrate, the ferrous sulfate and the humic acid are used for preparing a medium trace element chelate fertilizer, the urea, the water-soluble monoammonium phosphate and the potassium sulfate are added into the chelate fertilizer, the mixture is smashed and screened and is mixed with a solution to perform spray granulation, and a granulated material is dried, screened and cooled to obtain the humic acid fertilizer for correcting the lemon yellowing. The humic acid fertilizer for correcting the lemon yellowing integrates the humic acid, massive elements, medium elements and trace elements. The trace element utilization rate of the citric acid is improved, and the phenomenon that lemons are lack of essential elements and accordingly get yellow is effectively avoided. The humic acid fertilizer for correcting the lemon yellowing has fast-acting property and has remarkable economic, social and ecological benefits, fertilization times are decreased, the working efficiency is improved, and the labor cost is reduced.