Foliage from Hydrangea serrata (Amacha group) dried and used for tea. Cultivar names that include the word 'amacha' - Japanese for 'sweet tea' - are used in favour of other Hydrangeas which may contain the toxin hydrangin, related to cyanide. H. serrate 'Yae no amacha', meaning 'double sweetened tea', is recommended as an attractive double-flowering cultivar which may also be used for tea.