Farm and orchard waste feed the millions of worms on the commercial worm farm Robbie Dick has operated for 17 years in Cromwell, Central Otago.
There’s never a shortage of food for the worms. As the seasons changes so does the menu for the worms.
Wintering waste comes from dairy farms in Southland, while local growers supply hundreds of tonnes of apples, cherries, stone fruits, carrots and other surplus to requirement perishable goods that used to go into landfills.
Twenty tonnes of tiger worms are housed in sixty metre rows that are covered in old carpets. They eat through 28 tonnes of food every ten days and every 30 days they double in number.
“There’s about 2,000 varieties of worms but only seven are suitable for composting and the tiger worms seem to suit our conditions as they can take the warm and cold. But they won’t eat much if they are cold, so that’s why it pays to keep them as warm as possible over winter”.
The waste is converted into castings manure, organic compost and a natural alternative to fertilisers. It is bagged onsite and sent all over the country.
The worms themselves are sold to plumbers for composting toilets, people who are building their own worm farms and in much larger quantities to abattoirs for turning offal waste into compost.
To show visitors the impact the castings manure has on the growth of everyday plants, Robbie has built a trial area the back of farm.
“We’ve got ongoing trials with ryegrass with and without castings, swedes, the bulb of the swedes is three times bigger with the castings than without” he says with a big grin.