Tropical plant fool put in wine (7)
I believe the answer is:
cassava
'tropical plant' is the definition.
(South American shrub)
'fool put in wine' is the wordplay.
'fool' becomes 'ass' (ass is a kind of fool).
'put in' is an insertion indicator.
'wine' becomes 'cava' (type of Spanish wine).
'ass' put within 'cava' is 'CASSAVA'.
(Other definitions for cassava that I've seen before include "Manioc, source of tapioca" , "Root crop of the tropics" , "Edible starchy root" , "starchy type" , "Tropical food" .)