EVOLUTION N 13 is a fertiliser obtained from two organic matrices characterised by the presence of a high protein content: dry blood and hydrolysed leather. Dry blood, rich in amino acids, humic acids and iron (Fe) chelated to the organic matter, provides organic nitrogen (N) easily available, which is mineralised in the first few weeks after application. At the same time, the hydrolysed leather gradually releases the remaining organic nitrogen through a gradual and constant mineralisation process over time (3-4 months), ensuring continuous and prolonged nutrition, also reducing nitrogen losses due to leaching and gasification. This exclusive formulation makes EVOLUTION N 13 suitable for all herbaceous crops, horticultural crops (including protected crops) and trees, representing an innovative solution for nitrogen fertilisation in organic farming and allowing all the nutritional needs of plants in the various phenological stages.