The invention discloses a special liquid rooting fertilizer for vegetables as well as a preparation method and an application of the special liquid rooting fertilizer. The rooting fertilizer consists of the following components in parts by mass: 100-150 parts of potassium nitrate, 100-150 parts of urea, 100-150 parts of potassium dihydrogen phosphate, 40-80 parts of fulvic acid, 10-50 parts of molasses, 10-50 parts of calcium ammonium nitrate, 10-50 parts of composite amino acid solution, 5-10 parts of ethylene diamine tetraacetic acid (EDTA) iron, 5-10 parts of ethylene diamine tetraacetic acid (EDTA) zinc, 5-10 parts of boric acid, 5-10 parts of sodium alginate, 5-10 parts of alpha-pimacol and 500-800 parts of water. The rooting fertilizer disclosed by the invention, through mutual matching and combined action of various components and contents, can achieve a remarkable rooting effect, and is simple and convenient to use, and is a product which is remarkable in effect on promoting root development of the transplanted vegetables.