Last year, the global demand for matcha put an unprecedented strain on Japan’s tea industry, and it’s likely to happen again.

Murmurs of the “matcha shortage” have been circulating since last fall, when well-known Kyoto tea companies Ippodo and Marukyu Koyamaen announced purchase limits on the finely ground tea powder for the first time. Tourists and local consumers found many stores completely sold out of certain products from these companies and others.

The products that are scarce or sold out are mostly first-flush matcha (tea powder made from the first harvest of tea leaves of Camellia sinensis, the plant species that matcha is made from), which was historically used only for tea ceremonies but is now preferred by international consumers for everyday use. This matcha is harvested only once a year, so it’s especially limited. But the demand is still booming for other types as well.