Following the earlier note about maidenhair fern (Adiantum) being used in the production of drinks, the following might be of interest.
In her Thin Paths, 2011: 247, describing life in an isolated village in north Italy in about 2000, Julia Blackburn writes of a local man born in 1925 who:
‘admires the maidenhair ferns, which he tells me makes a good drink, boiled in water, when you have trouble with peeing’ [James Banks, Poole, Dorset, October 2012].

Image:  Sevenoaks, Kent; June 2015.