Evergreen limes set for cultivation (8)
I believe the answer is:
timeless
'evergreen' is the definition.
(evergreen can mean timeless or eternal)
'limes set for cultivation' is the wordplay.
'for cultivation' indicates an anagram.
'limes'+'set'='limesset'
'limesset' is an anagram of 'TIMELESS'.
(Other definitions for timeless that I've seen before include "Enduring" , "Lacking limits" , "Immutable" , "Never changing" , "permanent" .)