Biodynamic farming is the oldest organic farming movement in Germany. Since Dr. Rudolf Steiner’s “Course on Agriculture” held in 1924, the number of biodynamic farmers in Germany has grown continuously, with 1,317 farmers currently producing on 47,592 ha. One of the most distinctive aspects of biodynamic farming is the use of the so-called biodynamic preparations, which are applied in homeopathic doses. Biodynamic preparations are supposed to improve plant growth and food quality, minimising natural variations. This paper deals with investigations of influences of these preparations and increased manure application on potato yield and tuber quality. The results are drawn from extensive research on organic potato production carried out by several institutes of the University of Bonn, sponsored by the Deutsche Forschungsgemeinschaft (Bonn), and the Eden Foundation (Bad Soden)
