NOVELTY - Special fertilizer comprises (in pts. wt.): grain (10-20); monoammonium phosphate (15-17); ammonium sulfate (10-12); potassium sulfate (10-12); plant ash (16-18); manganese sulfate (20-30); ferrous sulfate (1-2); magnesium sulfate (1-2); zinc sulfate (1-2); borax (0.1-0.5); ash (0.1-0.3); charcoal (10-12); unbracteolated spurge root powder (5-7); radix stemonae (3-4); bagasse (3-4); volcanic rock (10-15); dairy manure (10-15); carboxymethyl cellulose (18-22); 30% of sulfuric acid (15-20); lime (5-10); lard (10-15) and cotton seed oil (4-6).    USE - The fertilizer is useful for sweet potato (claimed).    ADVANTAGE - The fertilizer has high utilization rate, reduces the pesticide residue, and improves the yield and quality of the sweet potato.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparing the fertilizer, comprising (1) hydrolyzing pig hair with 30% of sulfuric acid at 100-110 degrees C for 1-2 hours to generate amino acid and then dissolving/adding lime, carboxymethyl cellulose, manganese sulfate, ferrous sulfate, magnesium sulfate, zinc sulfate and borax to neutralize a pH value to 6-6.8 at 90-105 degrees C for 5-6 hours to generate amino acid chelate and a fertilizer solution, (2) sintering the generated amino acid chelate at 400-500 degrees C for 6-8 hours and grinding 1-2% of cotton seed into a powder and then mixing with plant ash as fertilizer carrier, (3) composting an organic fertilizer, vinasse, bagasse and dairy manure under high temperature condition, adding the composted mixture into Bacillus subtilis after mixing and then piling and fermenting at 60-65 degrees C for 5-10 (preferably 30) days to obtain the fermented organic fertilizer, (4) mixing/crushing the ammonium bicarbonate, phosphate and coated potassium sulfate with volcanic ash and charcoal and smashing/grinding the fermented organic fertilizer into 100-200 sieves, (5) mixing the biological pesticide unbracteolated spurge root powder and the radix stemonae powder to obtain the amino acid chelate, spraying the fertilizer solution on the mixed material and then completely stirring after granulating, and finally spraying the cotton seed oil to film to obtain the fertilizer.