Vaccinium uliginosum

Also known as Dianguo and Diguo. Ericaceae, evergreen dwarf shrub. Most of them are born in tundra zone, a high mountain, with alternate leaves and obovate leaves, and 1 ~ 3 flowers are often gathered in the branches or axils of last year. The flowers are small, bell-shaped and green-white; Berry oval or hemispherical, blue-purple, with hoarfrost. It blooms in June and bears fruit in July and August. Fruit can be eaten raw, brewed or made into jam. Leaves can be used as medicine, which has the effects of clearing away heat and astringing.
Reprinted with attribution： https://cnlocality.com/(Chinese Specialty Products)