Worms turn grape waste to good use

A central Otago vineyard is embracing worms as the secret to turning wine by-product into fertilising “black gold”. Mt Difficulty in Bannockburn this year bought 60kg of tiger worms to convert composted grape marc, made from grape seeds, skins and stalks, into vermicast, or worm poo. Mt Difficulty viticulturist James Dicey said vermicast was filled with nutrients and known as “black gold”.