Water retention type compound fertilizer and preparation method thereof

The invention relates to a water retention type compound fertilizer, which is prepared from the following ingredients in parts by weight: 50 to 130 parts of coated urea, 12 to 21 parts of calcium superphosphate, 6 to 18 parts of ammonium chloride, 8 to 20 parts of potassium chloride, 12 to 25 parts of sweet potato type citric acid residues, 6 to 30 parts of distillers' grains, 3 to 18 parts of EDTA (Ethylene Diamine Tetraacetic Acid) chelated zinc, 4 to 20 parts of amino acid chelated iron, 11 to 24 parts of plant growth regulator and 7 to 25 parts of anti-blocking agent. The compound fertilizer disclosed by the invention can meet the requirements of crops on nutrients, is reasonable in proportioning, slowly releases nutrients, improves the utilization rate of the fertilizer, promotes the crops to absorb nutrients, enhances the stress resistance of the crops, and reduces soil hardening and environmental pollution caused by fertilizer loss. 本发明涉及一种保水型复合肥，以重量份计，包括包膜尿素50-130份、过磷酸钙12-21份、氯化铵6-18份、氯化钾8-20份、甘薯型柠檬酸渣