Brewer's flowers (4)
I believe the answer is:
hops
'brewer's flowers' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for hops that I've seen before include "Beer flavouring" , "what could make you bitter" , "Skips" , "Dances -- beer ingredient" , "Leaps on one leg" .)