vervain Verbena officinalis, a European plant with greyish leaves and small lilac flowers, has enjoyed a medicinal reputation since antiquity. It is now used to make one of the better-known herbal teas or tisanes, which is slightly bitter but may be sweetened with honey.
© the Estate of Alan Davidson 1999, 2006, 2014 © in the Editor’s contribution to the second and third editions, Oxford University Press 2006, 2014.