Hydrangea serrata is a species of flowering plant in the family Hydrangeacea, native to mountainous regions of Korea and Japan. Common names include mountain hydrangea and tea of heaven. Growing to 1.2 m (4 ft) tall and broad, it is a deciduous shrub with oval leaves and panicles of blue and pink flowers in summer and autumn (fall). It is widely cultivated as an attractive ornamental shrub throughout the world in areas with suitable climate and soil.