NOVELTY - Organic liquid fertilizer comprises 0.005-0.15 wt.% microorganism A, 0.5-5 wt.% black sugar molasses, 0.15-1.5 wt.% carcass protein, 0.005-0.15 wt.% microorganism B, 0.25-0.5 wt.% protamine, 0.15-1.5 wt.% liver or bile animal organs, 0.05-1 wt.% sodium alginate and water. Microorganism A comprises Azotobacter, nitrifying bacteria, phosphorus solubilizing bacteria, microzyme, lactic acid bacteria, photosynthetic bacteria and actinomycetes.    USE - Organic liquid fertilizer used for promoting rootstalk enlargement (claimed).    ADVANTAGE - The organic liquid fertilizer reduces height of plant, increases yield, and has disease prevention effect.    DETAILED DESCRIPTION - Organic liquid fertilizer comprises 0.005-0.15 wt.% microorganism A, 0.5-5 wt.% black sugar molasses, 0.15-1.5 wt.% carcass protein, 0.005-0.15 wt.% microorganism B, 0.25-0.5 wt.% protamine, 0.15-1.5 wt.% liver or bile animal organs, 0.05-1 wt.% sodium alginate and water. Microorganism A comprises Azotobacter, nitrifying bacteria, phosphorus solubilizing bacteria, microzyme, lactic acid bacteria, photosynthetic bacteria and actinomycetes. Microorganism B comprises Bacillus subtilis, lactic acid bacteria, Aspergillus, microzyme, protein decomposing enzyme and starch decomposing enzyme. INDEPENDENT CLAIMS are included for:    (1) a method for preparing organic liquid fertilizer, which involves mixing microorganism A, black sugar molasses and carcass protein with water and fermenting for 30-60 days to obtain liquid composition A, mixing microorganism B, black sugar molasses, protamine, liver or bile of animal and sodium alginate with water and fermenting for 30-60 days to obtain liquid composition B, mixing liquid composition A and liquid composition B for 10-30 days, and then adding remaining components; and    (2) a method for application of organic liquid fertilizer, which involves diluting organic liquid fertilizer with water by 300-800 times, and spraying on ground part of crop during flowering period or nutrient or growth 1-3 times before 10:00 am or after 15:00 pm.