One who cultivates a road with new green borders (8)
I believe the answer is:
gardener
'one who cultivates' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'a road with new green borders' is the wordplay.
'road' becomes 'rd' (abbreviation).
'with' is a charade indicator (letters next to each other).
'new' is an anagram indicator.
'borders' is an insertion indicator (inserted letters are bordered by others).
'green' with letters rearranged gives 'gener'.
'a'+'rd'='ard'
'ard' placed into 'gener' is 'GARDENER'.
Can you help me to learn more?
(Other definitions for gardener that I've seen before include "Horticulturalist" , "He tends flowers and shrubs" , "Cultivator" , "Nursery employee" , "Weedy type" .)