The invention relates to a process for preparing a composite with fertilizing action. According to the invention, the process comprises the alkaline hydrolysis of leather wastes from hide liming in a float of 200% industrial water to which 3...7% KPOand 18...30% green biomass are admixed, at a temperature of 80...95°C, for 4...6 h, after which 0.5...1% corn starch and 0.3...1% boric acid are added, to result in a biocomposite which is admixed with 50...150% dry soil to finally obtain a green biocompost meant to be used as a nutritional support.
