Gather the harvest (4)
I believe the answer is:
reap
'gather the harvest' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for reap that I've seen before include "Get -- derive" , "'As you sow, so shall you . . . .'" , "''As you sow, so you . . . .'' (4)" , "Save harvest, glean" , "Cut or gather (a harvest)" .)