New leaf let go in French bean (9)
I believe the answer is:
flageolet
'french bean' is the definition.
'new leaf let go' is the wordplay.
'new' is an anagram indicator.
'leaf'+'let'+'go'='leafletgo'
'leafletgo' with letters rearranged gives 'FLAGEOLET'.
'in' acts as a link.
(Other definitions for flageolet that I've seen before include "Small flute" , "Blow me" , "Type of recorder" , "instrument is played" , "Pipe" .)