Add to ORKGAgriculture faces the challenge of producing high yields to feed a growing world population, while simultaneously addressing environmental problems such as eutrophication, emissions of greenhouse gases, loss of biodiversity and soil degradation. Organic farming can be part of the solution, as it promotes biodiversity, uses less energy for fertiliser production and often has higher inputs of organic matter to soil than conventional farming. However, yields are often lower, partly due to asynchrony in mineralisation of organic nitrogen (N) and crop acquisition. Growing legumes for protein production and input of biological N2 fixation to supply the cropping system with N is a common practice on organic farms. The addition of reactive N to the...