Biodynamic farming is the agricultural practices and philosophy that grew out of a course of eight lectures presented by the Austrian philosopher Rudolf Steiner (1861-1925) in June of 1924 at Koberwitz (it was then eastern Germany, it is now Kobierzyce, Poland).  Steiner sought to steer agriculture away from the path of chemical agriculture and away from synthetic fertilisers.
At the Koberwitz lectures, Steiner founded the Experimental Circle of Anthroposophic Farmers and Gardeners. The task of the Experimental Circle was to put Steiner's farming ideas to the test and to develop them into a form suitable for publication. That was achieved in 1938 when Dr Ehrenfried Pfeiffer published his book, Bio-Dynamic Farming and Gardening. 
Biodynamic agriculture has developed a following around the world in its own right. But even more importantly, it influenced Lord Northbourne to develop Steiner's idea that the farm is an organism and to coin the term 'organic farming' in his 1940 book, Look to the Land. 
Biodynamic farming and organic farming alike avoid the use of synthetic fertilisers and pesticides, food irradiation, nanotechnology, and genetically modified organisms (GMOs).
Notes and references
- Steiner, Rudolf. (1924). The Agriculture Course (first English edition was 1929). Dornach: Goetheanum.
- Paull, John (2011) "Attending the First Organic Agriculture Course: Rudolf Steiner’s Agriculture Course at Koberwitz, 1924", European Journal of Social Sciences, 21(1):64-70.
- Pfeiffer, Ehrenfried. (1938). Bio-Dynamic Farming and Gardening, New York: Anthroposophic Press.
- Paull, John (2011) "The secrets of Koberwitz: The diffusion of Rudolf Steiner’s Agriculture Course and the founding of Biodynamic Agriculture", Journal of Social Research & Policy, 2(1):19-29.
- Northbourne, Lord. (1940). Look to the Land, London: Dent.
- Paull, John (2014) Lord Northbourne, the man who invented organic farming, a biography, Journal of Organic Systems, 9 (1), pp. 31-53.