Vegetable gold, black and green, I gathered (9)
I believe the answer is:
aubergine
'vegetable' is the definition.
(aubergine is a kind of vegetable)
'gold black and green i gathered' is the wordplay.
'gold' becomes 'au' ('Au' can be a synonym of 'gold').
'black' becomes 'b' (as in pencil classifications).
'and' says to put letters next to each other.
'gathered' indicates anagramming the letters.
'green'+'i'='greeni'
'greeni' with letters rearranged gives 'ergine'.
'au'+'b'+'ergine'='AUBERGINE'
(Other definitions for aubergine that I've seen before include "Edible plant" , "I agree bun could become a strange vegetable" , "Fruit cooked and eaten as a vegetable" , "I argue, Ben, that it's a fruit" , "Purple vegetable" .)