A vine somehow turned green (5)
I believe the answer is:
naive
'turned green' is the definition.
'naive' can be an answer for 'green' (green can mean naive or innocent). I am not sure about the 'turned' bit.
'a vine somehow' is the wordplay.
'somehow' indicates an anagram.
'a'+'vine'='avine'
'avine' with letters rearranged gives 'NAIVE'.
Can you help me to learn more?
(Other definitions for naive that I've seen before include "Rather too simple and ingenuous" , "Callow" , "Inexperienced or gullible" , "Wet behind ears" , "Unenlightened" .)