Lettuce grown at the Felix Thomas REWE supermarket in Lankwitz, Berlin.
Photograph: Christoph Große Customers seeking greens at one Berlin outlet are dealing with some very local supply chains indeed By Hannah Docter-Loeb Walking into the Felix Thomas REWE supermarket in Lankwitz, Berlin, customers are immediately presented with a choice of greens: romaine, rocket, iceberg.
But last month, a new option joined the selection: Lankwitz loose-leaf lettuce.
A combination of head lettuce, romaine lettuce, Lollo Rosso, and dark green easy leaf lettuce, its yellow packaging makes it stand out in a row of green.
But it’s not just the flashy packaging that makes it distinct.
Unlike its neighbouring lettuces, which come from regional farms or all the way from Italy, these greens were grown just a few metres away – or rather, a few metres up.
“Frisch Vom REWE Dach” or “Fresh from the REWE roof”, the bags read.
Rooftop farms are nothing new: in cities such as Paris, Hong Kong, Copenhagen and New York, similar farms supply food to adjacent food retailers or even restaurants.
This model has the potential to reduce greenhouse gas emissions from transportation (and its associated costs), minimise the urban heat effect, make use of dead space and perhaps even improve the relationship between buyers and their food.
Germany is also no stranger to rooftop farms.
In 2021, REWE and ECF – a Berlin-based agricultural technology company – opened their first green farming market on top of a store in Wiesbaden-Erbenheim, selling basil below.
But at 2,760 sq metres, the Lankwitz REWE is now Germany’s largest rooftop farm.
The Felix Thomas REWE supermarket was clearly designed with the farm in mind.
The Lankwitz lettuce has become a selling point of sorts: store manager Felix Thomas says one customer travelled more than 50km just to get their hands on a bag.
And the integration of the farm into REWE’s market and corresponding supply chain is novel, says ECF CEO and founder Nicolas Leschke.
The supermarket was clearly designed with the farm in mind: skylights throughout the store offer a window into what’s growing above.
“The cool thing about producing locally and on a building is you can create synergy within the building,” Leschke said.
The greenhouse is heated through the waste heat of cooling aggregates downstairs, and rainwater is the primary source of water for the greenhouse and plant production.
Some of the greenhouse is also powered by sustainable energy – primarily solar.
The operation is meant to be year-round.
The farm makes use of hydroponic technologies: the lettuce varieties are grown with very little soil.
The whole growing process takes a little over three weeks.
Once cut, the greens go straight downstairs to be packaged and sold, both on site and in other stores in the city and region.
The farm makes use of hydroponic technologies: the lettuce varieties are grown with very little soil, and the whole growing process takes a little over three weeks.
Photograph: Christoph Große “We don’t even have an extra truck on the road that usually is necessary to transport the goods from the producer to the central distribution,” Leschke said.
Prajal Pradhan, an associate professor at the University of Groningen in the Netherlands, who recently published a study on urban agriculture in Europe, sees REWE’s latest rooftop as a step in the right direction.
“There is a disconnection between producers and consumers,” he said.
“This is a way to go forward, because you can provide fresh vegetables to urban consumers on site.” However, he stresses, it should not be an alternative to having a personal or community rooftop garden.
He says urban agriculture should be inclusive and find ways to include the whole community, a sentiment echoed by study co-author Stepan Svintsov, a remote sensing expert based in Berlin.
“Getting people together from a dense city and sharing agricultural knowledge among them helps bring the community together,” Svintsov said.
REWE currently offers tours to see the facility from outside, but no one can enter the production rooms.
There is a large potential for rooftop farms and the like in Europe.
Pradhan, Svintsov and their colleagues’ review looks at the biophysical viability for urban agriculture in European cities: seeing how urban rooftop and ground-based areas are well suited for cultivating vegetables.
They found that urban agriculture in European cities could produce up to 20m tonnes of vegetables annually.
This translates to about 28% of the continent’s vegetable demand. skip past newsletter promotion after newsletter promotion Skylights throughout the store offer a window into what’s growing above.
Photograph: Christoph Große Pradhan also previously co-authored a study that showed how a large share of Berlin’s vegetable consumption could be produced within the city.
“This [supermarket] could also be an inspiration for other people to do something together,” says Pradhan.
Leschke’s ambitions are bigger than just Berlin.
He hopes to build at least 20 supermarket rooftop farms over the next 10 years, and ideally at least one in every REWE region in the next five years.
“If we can produce in Germany year-round, we should,” he said, emphasising the importance of becoming independent of global supply chains.
But for now, that does not seem to be on customers’ minds.
At the salad display, a customer eyes the selection, opting for two bags of the Lankwitz lettuce.
Another makes a beeline for the local variety.
As she explains, she’s making a salad of tomato and mozzarella later, and she likes the idea of using the greenhouse greens.
After all, it’s fresh from the roof.
The rooftop greenhouse at the Felix Thomas REWE supermarket in Lankwitz, Berlin.
