A 1,260-sq.-meter factory in Kashiwanoha, Chiba Prefecture, is kept extremely clean, shutting out external air because it affects product quality, and workers wear clean-room suits and take a warm shower before entering the facility.

What are they making there — semiconductors or some kind of high-tech machinery?

No, they are actually growing vegetables on layers of shelves neatly set up on 5-meter-high racks.