One of the most frequently asked questions I get is "What is 500?", so here's my short and simple explanation on how I use biodynamic preparation 500 for those who haven't heard of it before. 

(BD farmers please forgive the simplicity). Preparation 500 is manure placed in a cow horn,  buried in a well drained pit over the winter and then brought up in the spring, in which the manure turns into a sweet colloidal material, full of billions of probiotic microbes for making humus in the soil.

I purchase my 500 from expert farmers who do this work properly and who have many years experience doing so. I then store it in clay pots, in an insulated box to keep the microbes cool and moist. (If the microbes get too dry they will die and the 500 is then useless)  I usually do 500 spraying in spring and autumn when the soil is warm and moist for maximum efficiency. Too hot, the microbes could die from dryness, too cold they will be less efficient and could die in a frost.  I warm water to 35c (to help activate the microbes from their dormant state) in a copper tank with a gas or wood flame because if I use electrical heated water I feel I risk damaging the effectiveness of the process.  The warm water goes into a stirring machine (made from copper or stainless steel) where the 500 is added. The machine stirs it through a vigorous series of vortexes for an hour so the maximum amount of air is added and the aerobic 500 microbes are activated and enlivened.

The mix goes into a copper spray tank ready to be applied to the paddock. I strain out the the larger composted manure particles using a strainer so as not to block the spray nozzles but with large enough holes to let the larger biology and worm eggs through. The reason I use copper or stainless steel tanks in all these processes is that i don't want to kill the life in the 500 from a plastic tank as they can excrete some toxins.

I put the spray out after 2 pm and into the evening using a diaphragm pump so the microbes aren't destroyed going through an impeller of a high pressure pump. I spray at low pressure through special large nozzles, so large droplets form and allow the 500 to fall to the ground better and contact the soil, (also to let larger microbes and worm eggs through). Here they will grow and multiply and eat all the organic matter like old root systems, old grass and manure. Then in time, turn it all into humus, (a colloidal compost material full of nutrients), natures plant food. 

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