The UK’s first underground farm is protected from the vagaries of the weather but not, it turned out, from another perennial problem for farmers: trespassers.
The appearance of spray-painted squares on the floor of the former air raid shelters under Clapham in London mystified Steven Dring, co-founder of Growing Underground: “Then someone said to me ‘that’s where the speakers were going to go for a rave’.”
Stronger doors were quickly put in and the farm is now producing daily crops of herbs which go the the capital’s fresh produce market at New Covent Garden and a home delivery service. The aim of the company, said Dring, is to help address the looming issues of growing population, increasing food demand and sustainability in farming.
The advantages of underground farming are a controlled environment and being very close to the market. Dring said his fresh herbs can be on a restaurant plate within four hours of harvesting and 24 hours at most.
The seed of the idea was formed when Dring and business partner Richard Ballard, who had been discussing the challenge of sustainability in the pub, saw a book on vertical farms. But, even during the recent recession, rents for city tower blocks were too high. Then Ballard, then a film student, encountered the Clapham tunnels while location-scouting for a shoot.
The tunnels, built as air raid shelters in world war two, are 120 feet under the surface and vast: 65,000 square feet and able to harbour 8,000 people. Now, one of the tunnels hosts trays of sprouting herbs. This list of produce is long and includes pea shoots, rocket, wasabi mustard, red basil and red amaranth, pink stem radish, garlic chives, fennel and coriander.

After germination in a dark, humid section of tunnel, the trays are brought into the light and grown hydroponically. The herbs are grown on mats made from carpet offcuts and fed with nutrient-laden water, 90% of which is cleaned and recycled.
Dring said the project would not be viable without low-energy LED lights: “The only reason we can do this is because of the improvement of in technology in the last five years.” Currently the subterranean farm can produce up to 2,000 packs a day, each with 30g of herbs.
The company has raised £1.2m so far, partly via crowdfunding, and has major salad firm G’s as an investor and Michelin-starred chef Michel Roux Jr as a co-director. “The herbs will certainly be a fixture on the menu at [my restaurant] Le Gavroche,” said Roux, who happens to live almost directly above the tunnels.
London mayor, Boris Johnson, has also backed the project: “This is a fine example of the dynamic startups that are helping London lead the world in green business innovation.”
“Rich [Ballard] wanted to change the world. I didn’t,” said Dring, who used to work in catering logistics. Instead, Dring said, he wanted to show sustainable businesses can be profit-making and not need subsidies. It is early days still and the company will publish its first carbon accounts in June. Despite the much lower transport emissions which their city-centre location enables, Dring does not expect the farm to be carbon-neutral and will offset its emissions via a robust forestry scheme.
Growing Underground began with fresh herbs because of their high value but expects to move into salad crops next. Dring describes the underground operation as having created new farmland but acknowledges that conventional farming is not going to be threatened by it soon. “We will only be complementary to farming, but if you grow fresh produce like salads and herbs right near people, then the fields can be used for more potatoes, carrots and so on.”

Dring said there is an increasing interest in hydroponic growing in warehouses, especially in China and Japan, but he did not know of any other underground farms. Interest in urban farming is growing and other novel approaches include Farmed Here, a vertical farm near Chicago, and Freight Farms, which creates ready-made hydroponic farms inside a shipping container.
Dring welcomed the competition: “It encourages us that we have not gone too leftfield.” But he said there was still plenty of work to do to build his business and develop sustainable urban farming.
For example, he said: “We can’t get organic status because the produce is not grown in soil.” Getting good quality organic nutrients for the hydroponic system is also a problem: “At the moment, we are using stuff from the petrochemical industry and that doesn’t sit well with us.”