Germany's Largest Rooftop Farm Opens in Berlin

Berlin just got its first supermarket that grows its own lettuce on the roof. REWE has opened its new Green Farming Berlin store in Lankwitz, and according to the company's press release, the site now hosts Germany's largest rooftop farm at 2,760 square meters.

Starting this summer, the rooftop greenhouse will produce Lankwitz pick lettuce, a mix of Kopfsalat, Römersalat, Lollo Rosso and dark green Easy Leaf varieties. The plants grow hydroponically, almost without soil, on trays flooded several times a day with a nutrient solution. From harvest to store shelf, it takes just 23 days. Once running at full capacity, the farm could produce up to 900,000 salad mixes a year, supplying around 500 supermarkets across the Berlin region. The rooftop farm is operated by Berlin based ECF Farmsystems, founded by Nicolas Leschke. ECF builds and runs aquaponic and hydroponic farm systems for food retailers more broadly, growing everything from basil to trout, and it uses lifecycle assessments to track the environmental footprint of each project as it scales up.

Inside, the market itself is built almost entirely from wood: 72 columns of stacked timber beams form the hall, using 1,800 cubic meters of regional softwood that stores 930 tonnes of CO2 equivalent. Waste heat from the store, a heat pump and rainwater collected in a cistern help keep the rooftop farm running, while around 200 solar panels and 100 percent green power cut energy use by half compared to standard supermarkets.

The design comes from a ten year collaboration between REWE and architecture firm ACME, building on REWE's Green Building program that started in Berlin-Rudow back in 2009. REWE says this modular wood construction is now going into serial production, with more timber markets planned across Germany.