Flower; instrument (5)
I believe the answer is:
viola
I believe this clue is a double definition.
'flower' is the first definition.
(I've seen this before)
'instrument' is the second definition.
(viola is a kind of instrument)
(Other definitions for viola that I've seen before include "One played" , "part of Shakespeare" , "Pansy-like flower" , "big fiddle!" , "Page" .)