In the Netherlands the fertilisation within the cultivation of potatoes on average consists of a combination of manure with synthetic fertilisers. This is due to on the one hand legislative limitation of use of nitrogen amount out of manure. And also the use of synthetic fertilizer provides a better controllable fertilization of the crop throughout the season, compared to mineralization of manure which is partly dependent on environmental factors. However, the production of chemical fertilizer is considered to have a large environmental impact. In addition, there is a large availability of manure in the Netherlands. A solution for these contradictive facts might lay in the development of so called RENURE, Recovered Nitrogen from Manure. Within this method, manure is processed and split up into organic fraction and an inorganic fraction. The inorganics fracture consists of ammonium nitrate or ammonium sulfate, which can be used in fertilisation of potatoes. This provides the controllability of a synthetic fertilizer, optimizing the use of nutrients while on the other hand having less impact on environment and helps closing the nutrient cycle within agriculture.