Ivy for one always the ingenue? (9)
I believe the answer is:
evergreen
'ivy' is the definition.
(I've seen this before)
'one always the ingenue?' is the wordplay.
'one always' becomes 'ever' (I've seen this in another clue).
'the ingenue?' becomes 'green' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'ever'+'green'='EVERGREEN'
'for' is the link.
Can you help me to learn more?
(Other definitions for evergreen that I've seen before include "Non-deciduous tree - always immature?" , "box, perhaps" , "Leaves of holly and ivy are --" , "pine maybe" , "Always popular" .)