KYOTO, Japan — Jintaro Yamamoto grows and sells green tea much in the same way his elders did before him since the family business began in the mid-19th century.

For one, the family’s store in Uji, just southeast of the city of Kyoto, still sells tencha, the dried tea leaves that are ground up to make matcha, rather than just the more-profitable powdered final product. For another, before harvesting the leaves in the spring, Yamamoto shades them for a few weeks with straw and other natural materials rather than the black plastic sheeting now used on most Japanese farms. Then each year in May, he and a group of neighbors pick the ripened leaves by hand, instead of by machine.