The building on the Middle Littleton site features a curved roof planted up as a wild flower meadow, intended to blend in with the surrounding hills.
Surplus rainwater is harvested for use in the building, while the walls are made of hempcrete, which is claimed to be both sustainable and highly insulating.
Kanes Foods commercial director Jeremy Folkard told Grower: "We have key specialist growers with whom we have worked for years and who are keen to grow with us. We have the potential to increase output by 50 per cent next year."
The company supplies bagged salads to supermarkets. "That market has seen double-digit growth but that is now slowing," according to Folkard.
"The challenge now is to convert those customers who still buy whole-head lettuce," he added.