The company's website says:
At Growing Underground, we sustainably grow mouth-wateringly fresh micro greens and salad leaves 33 metres below the busy streets of Clapham. Using the latest hydroponic systems and LED technology, our crops are grown year-round in the perfect, pesticide-free environment that these forgotten tunnels provide. Thanks to a controlled environment, each tiny leaf tastes as amazing as the last. Our greens are unaffected by the weather and seasonal changes, and thanks to our prime location, we reduce the need to import crops and drastically reduce the food miles for retailers and consumers.The do tours that you can book on Eventbrite. I am sure one must be in my future as I continue to try and bank one interesting trip a month well in advance.