Koberwitz, Whitsun 1924: Rudolf Steiner had just completed his momentous lecture course on biodynamic agriculture and was waiting for a car to take him to the station. Suddenly he was approached by two of his pupils with an urgent question: Would his new indications for treating soil and vegetables be sufficient to provide, '...nutrition appropriate to our times and in accordance with the spirit?' Steiner's frank response was somewhat surprising: 'It will not be sufficient even in the most favourable circumstances. What should be done is to cultivate the Dioscorea batatas in Europe so that it...