Once you have got the indoor-growing bug, there is almost no limitation as to where you can actually set up your indoor garden, and if you do it in the right place, the endeavour can even be quite profitable too. Just ask the founders of Growing Underground, who have recently set up an indoor farm over 30m below the streets of London in a disused World War II air-raid shelter of all places. Crucial to its success is its proximity to lots of food markets and eateries allowing them to carve out a niche in London’s fresh produce market by producing ultra-fresh produce that tastes better and is more nutritious since only having been harvested just a few hours earlier. Growing Underground is the creation of Richard Ballard and Steven Dring, two entrepreneurs that spotted a gap in the London fresh produce market but they also have some pretty impressive directors on their board including Chris Nelson, a consultant well-known in the horticultural arena, and Michel Roux Jr., the chef patron of the Michelin-starred Mayfair restaurant, Le Gavroche. The growing tunnels themselves are located underneath London Underground’s Northern Line where the farm remains isolated from changes in seasonal variations in surface climate allowing produce to be grown year-round. In addition, the underground location is not accessible to typical farming pests and diseases so pesticides are unnecessary making the produce even more desirable. Unsurprisingly, the founders have opted for using hydroponics to make the system as efficient as possible and to dramatically reduce their water requirements, and LED lighting is used to optimise growing conditions while keeping energy costs down. So far, Growing Underground has been successful in marketing Watercress, Thai Basil, Red Vein Sorrel, Pea Shoots, Mustard, Red Amaranth, Garlic Chive, Coriander, Mizuna, Rocket, and Radish, and the company is doing so well that it just recently secured further funding to expand into yet more underground tunnels.