Preparation method of special fertilizer for orange trees

The invention discloses a preparation method of special fertilizer for orange trees. The special fertilizer is prepared from raw materials in parts by weight as follows: 3-5 parts of plant straw, 3-5 parts of grass carbon, 6-10 parts of animal manure, 6-10 parts of urea, 5-10 parts of ammonium sulfate, 3-5 parts of calcium superphosphate, 5-8 parts of ammonium hydrogen phosphate, 4-6 parts of potassium chloride, 1-2 parts of borax, 1-2 parts of ammonium molybdate, 3-5 parts of ferrous sulfate, 0.4-1 part of manganese sulfate, 1-2 parts of zinc sulfate and 1-2 parts of magnesium sulfate, the raw materials are ground, fermented and granulated, and the special fertilizer is prepared. The fertilizer has a reasonable formula, most of fertilizer ingredients are absorbed by orange trees, and soil pollution is reduced while growth of the orange trees is guaranteed.