Jupiter’s Beard.
House-leek. Supposed to be a charm against evil spirits and lightning. Hence grown at one time very generally on the thatch of houses.
“Et habet quisque supra domum suum Jovis barbam.”—Charlemagne’s Edict.
· 
· 
Entry taken from Dictionary of Phrase and Fable, edited by the Rev. E. Cobham Brewer, LL.D. and revised in 1895.