Shigeharu Shimamura, 43, jointly runs a plant factory with Mitsui Fudosan Co. in Kashiwa-no-ha Smart City in Kashiwa, Chiba Prefecture, that can ship 10,000 heads of lettuce in one day, as well as herbs.
Lettuce is cultivated in a 1,260-square-meter room with a six-meter-high ceiling at the plant using hydroponic methods under artificial light. The tasty salad favourite takes about a month to grow.
Conventional vegetable factories face a range of problems, including declining product quality when priority is placed on production efficiency. But Shimamura’s operation involves precise control of lighting, water and fertilizer. His method allows mass production of lettuce that has “little bitterness and high nutritional value,” while also keeping costs down. A head of lettuce costs ¥200.