Feel air improved, more green (7)
I believe the answer is:
leafier
'more green' is the definition.
(green can mean leafy or verdant)
'feel air improved' is the wordplay.
'improved' indicates anagramming the letters.
'feel'+'air'='feelair'
'feelair' with letters rearranged gives 'LEAFIER'.
(Other definitions for leafier that I've seen before include "more rural" , "more green" , "Having more foliage" , "sort of suburb" .)