Grosset – a biodynamics sceptic converted

Stephanie Toole lifts a lid covering a square hole in the ground at the foot of her hillside vineyard in Watervale, in South Australia’s Clare Valley. Inside is a dark slurry of gently fermenting cow manure, mixed with crushed eggshells, basalt dust and tiny quantities of biodynamic preparations: stinging nettle, chamomile, oak bark.

This is what biodynamic farmers call a ‘cow pat pit’, a surprisingly sweet-smelling kind of supercharged fertiliser that Toole and the team who also manage the Grosset vineyard next door...