~Urban Mushroom Farm

The first urban mushroom farm opened by Rob Hopkins on the  23 September in Exeter. Rob said, “this really is a fantastic project - growing food from waste in the middle of a city. What an inspirational idea, and one that’ll spread to other cities I’m sure!” Half a tonne of spent coffee grounds are collected by bicycle and trailer, from local cafés within a very short distance of the farm, based in a disused office building in Exeter city centre. The coffee grounds are ideal for growing oyster mushrooms as they require a sterilised material to grow on and much of the energy used in mushroom farms is spent on the heating required to sterilise the substrate before the spawn is added. Coffee grounds, have of course been effectively sterilised by having boiling water poured over them. Because less than 1% of the coffee is actually extracted to make a cup of coffee the rest is just ‘waste’ however the grounds are rich in nutrients and ideal food for fungi. GroCycle, the team behind the idea, say the project is partly driven by the fact that coffee waste is such a huge environmental problem. Approximately 80 million cups of coffee are drunk every day in the UK, yet less than 1 per cent of the bean actually ends up in the cup. The vast majority of the remaining grounds are buried in landfill, decomposing to produce methane, which is 25 times more harmful to the
earth’s atmosphere than CO2. “It’s crazy that most large cafes are throwing their coffee waste away,” said Adam Sayner, company director. “It is still packed full of nutrients which can be turned into delicious Oyster mushrooms. We are making it possible to grow gourmet food from it instead!” Urban community composters and recycling projects could easily add growing oyster mushrooms to their activities and GroCycle do run training events to teach prospective mushroom growers how to do it. See www. grocycle.com for more information.     “Growing mushrooms in this way is absolutely ideal for Urban Agriculture,” said Eric Jong, company director. “It is where both the waste and demand for food are highest. We hope our farm will serve as a flagship model for more urban farms in the future.” To spread the concept further, the company has also devised a popular and simple to use grow-at-home kit – bringing the process of growing mushrooms from coffee grounds into people’s homes all around the country. More than 10,000 of these kits have been sold the last 2 years.