Summer's end is complete (5)
I believe the answer is:
total
This clue is a double definition.
'summer's end' is the first definition.
(I've seen this in another clue)
'is complete' is the second definition.
(similar in meaning)
(Other definitions for total that I've seen before include "Entirety" , "gross" , "Aggregate, sum" , "Reckon" , "Complete; add up" .)