Biodymics as a system is hard to appreciate, never mind understand, so I’ll start by recommending the most accessible book on the subject in case you want to know more. The best, easy to understand reference is Monty Waldin’s book Biodynamic Wines. Think organic double plus and you won’t go far wrong.
Biodynamics permits even less chemistry, but mandates the regular use of various composts and fermented products applied in homeopathic doses. Envisaged by Rudolf Steiner, who in turn was influenced by Goethe, biodynamics was an early reaction against the introduction of intensive, chemical farming in the early 20th century. The word comes from ‘bio’ – meaning composts and other naturally derived products, which have been diluted and ‘dynamised’. This latter involves creating alternate vortexes in the liquid to energise it. Biodynamic farmers operate on a lunar calendar, which is divided into days according to the kind of plant they are growing. The best days for working with vines are therefore fruit and flower days.
The founding principle of biodynamics is to have a farm, and especially the soil, full of life and with multiple organisms. This is mainly to encourage the phenomenon of mycorrhizal symbiosis, which is the interaction between plants and soil-borne fungi. This is as important to plants as photosynthesis and without it they do not thrive.