German supermarket grows 900,000 salads a year on its own rooftop

A Berlin supermarket is revolutionizing the way fresh salad is produced and consumed by cultivating lettuce on its own rooftop. The REWE Green Farming store, located in Berlin’s Lankwitz district, opened on May 21, 2026, and boasts a 2,760-square-meter rooftop farm capable of producing up to 900,000 salad mixes annually. The lettuce is grown, harvested, and packaged on site using hydroponic methods, eliminating the need for soil and reducing water usage.

Berlin-based ECF Farmsystems operates the rooftop farm, which is designed to produce food year-round using hydroponics and nutrient solutions. The lettuce grows on trays with a 23-day growing cycle and is ready for sale the moment it is harvested. This allows for a shorter supply chain, reducing transportation emissions and ensuring fresher produce for customers.

The rooftop farm not only saves around 500,000 transport kilometers annually compared to imported lettuce but also contributes to the store's eco-friendly design. The main structure is made of timber, and 200 solar panels generate renewable energy. Rainwater collected in a 200-cubic-meter underground cistern is used for both the store and farm, helping the supermarket cut energy consumption by around 50% compared to traditional supermarkets.

Although the Berlin store is Germany’s largest rooftop farm, REWE has already experimented with similar rooftop farming in Wiesbaden-Erbenheim since 2021. This innovative approach demonstrates how unused urban spaces like rooftops can contribute to local food production, offering fresh, locally grown lettuce with minimal travel time from farm to store.