Horn Silica (501)
We were up early this morning preparing biodynamic preparation 501 which is a Horn Silica spray. It is most effective if sprayed at sunrise, when the dew is still on the ground, so we met at 5.30am to prepare the mixture and Alex was on the vineyard spraying soon after 6.30am!
Horn Silica is used during the growing season to enhance growth and maturation. It is sprayed on the vine canopy to enhance the photosynthesis of the leaves to improve growth and maturation. It helps to stabilise plant metabolism and increases nutritive value. It can also strengthen the vines against attack by fungus.
It is prepared by making a paste using finely ground quartz crystals and water. This is placed in cow horn and buried during the Spring. Small amounts of the crystals are then dissolved into water and sprayed on the vineyard. The crystals enhance the effectiveness of light on the vines and so it is best sprayed on sunny days.