Cow horns | Horns from female cow are integral to Biodynamic farming. The horns are used as sheaths to make two of the nine so-called ‘preparations’ used in biodynamics. This are Horn manure 500 and Horn silica 501 which are used as field sprays. When Rudolf Steiner (1993, p79) was asked in the discussion after the fourth lecture of his Agriculture course about how many times cow horns could be used for the Horn manure he replied ‘as far as I can tell, you ought to be able to use the horns three or four times. After that, they probably won’t work as well.’ When Steiner (1993, p85) was asked if the horns could be used for both Horn manure ‘500’ and Horn silica ‘501’ he said ‘yes, you can do that, but you still won’t be able to use them more than three or four times. They lose their forces after having been used three or four times.’ Rudolf Steiner (1993, p79) did add that ‘it might be possible to use them for another year if you store [the empty horns] in the cow barn for a while after they’ve been used three or four times.’ Ideally, the horns would be hung in a string sack allowing air to get to them. As used horns are extremely difficult to break up they are usually buried beneath newly planted trees or shrubs, providing the plants with a long-term source of nitrogen.
Rudolf Steiner, Spiritual Foundations for the Renewal of Agriculture by Rudolf Steiner (Bio-Dynamic Farming and Gardening Association, Inc. USA, 1993), trans. by C. Creeger and M. Gardner.