End of spring, then meagre harvest (5)
I believe the answer is:
glean
'harvest' is the definition.
(I know that harvest can be written as glean)
'end of spring then meagre' is the wordplay.
'end of' suggests the final letters.
'then' is a charade indicator (letters next to each other).
'meagre' becomes 'lean' (I've seen this before).
The final letter of 'spring' is 'g'.
'g'+'lean'='GLEAN'
(Other definitions for glean that I've seen before include "Learn by gathering bits" , "Gather; collect gradually" , "Collect gradually (from various sources)" , "Garner" , "Gradually put together" .)