London air raid shelter becoming underground farm

Zero Carbon Farms grows herbs and lettuce in Clapham, south London, a heavily populated area without space for conventional farming.

But 30 metres underground there is a kilometre of tunnel, and technology has brought agriculture there to fruition.

Seven years after the first harvest it is poised to double its area, helping it respond to strong demand from major UK retailers such as Marks & Spencer (MKS.L) and local restaurants for their rump, arugula and watercress.

Shoppers appreciate both the freshness of the products that make it onto the plate of the restaurant during two hours following harvesting and their arrival on the city itself, without increasing emissions through air travel or long travel.

"The future is very, very bright for this industry and I think that what really is going to be the fundamental pivot point is the right application of technology," said Tommaso Vermeir, chief grower of the plant.

Zero Carbon Farms reckons it has an advantage over scores of other vertical farm projects coming into being in the UK, due to its permanent business and years of experience in providing higher yields through the new farmlands.