Money plant? (4)
I believe the answer is:
mint
'money plant?' is the definition.
'mint' can be an answer for 'plant?' (mint is a kind of plant). I am not sure about the 'money' bit.
'money plant?' is the wordplay.
'money' becomes 'm' (abbreviation in economics).
'plant?' becomes 'int' (I am not sure about this - if you are sure you should believe this answer much more).
'm'+'int'='MINT'
Can you help me to learn more?
(Other definitions for mint that I've seen before include "Aromatic herb - perfect" , "Large sum of money" , "A bomb" , "Fragrant herb" , "Place where coin money is made" .)