Biodynamic production was developed by Steiner. It represents one part of his total philosophy. You do not have to buy into the whole to use the gardening section.
It relies upon planting in relation to moon cycles into soil prepared for the seed using biodynamic specific additives.
It is, of course, an organic system with, proponents argue, higher standards than standard organic methods.
One particular additive is produced by anaerobically processing cow manure packed into cow horns and buried for a given time.