Unripe grapes are too much for her (3)
I believe the answer is:
peg
'her' is the definition.
(I've seen this before)
'unripe grapes are too much' is the wordplay.
'are too much' indicates the answer is hidden within the clue (the clue hides the answer plus unneeded letters).
'PEG' is hidden within 'unripe grapes'.
'for' acts as a link.
(Other definitions for peg that I've seen before include "Brandy and soda drink measure" , "Small cylindrical pin" , "Member" , "that may have hat or coat on" , "Wooden pin, small marker" .)