Time to leave local green (5)
I believe the answer is:
Here is my best explanation:
'green' is the definition.
('naive' can be similar in meaning to 'green')
'time to leave local' is the subsidiary indication.
'time' becomes 't'.
'to leave' is a deletion indicator.
'local' becomes 'native' ('native' can be similar in meaning to 'local').
'native' with 't' removed is 'naive'.
(Other definitions for naive that I've seen before include "Too innocent or gullible", "Dewy-eyed", "Too trusting and inexperienced", "Ignorant", "Unsophisticated and gullible", "Being unenlightened", "Inexperienced, gullable", "Credulous and innocent", "Unenlightened" and "Showing lack of experience or sophistication".)