Turn up again to harvest fruit (8)
I believe the answer is:
reappear
'turn up again' is the definition.
(I've seen this before)
'harvest fruit' is the wordplay.
'harvest' becomes 'reap' (synonyms).
'fruit' becomes 'pear' (pear is a kind of fruit).
'reap'+'pear'='REAPPEAR'
'to' acts as a link.
(Other definitions for reappear that I've seen before include "spring up again?" , "Be seen again" , "Turn up again" , "crop up again" , "Come into view again" .)