Growing plenty drunk (4)
I believe the answer is:
lush
I believe this clue is a double definition.
'growing plenty' is the first definition.
(lush can describe thriving or abundant vegetation)
'drunk' is the second definition.
(I know that lush is a type of drunk)
(Other definitions for lush that I've seen before include "Of grass, growing thick and strong" , "Growing luxuriantly, grass say" , "Flourishing - drunkard (slang)" , "Abounding in lavish growth - alcoholic" , "Luxuriant; very rich" .)