Grapes mostly cultivated outside over large garden feature (7)
I believe the answer is:
pergola
'garden feature' is the definition.
(I've seen this before)
'grapes mostly cultivated outside over large' is the wordplay.
'mostly' means to remove the last letter (most but not all of the word).
'cultivated' indicates anagramming the letters.
'outside' indicates putting letters inside.
'over large' becomes 'ol' (this could be a standard abbreviation I've not previously seen).
'grapes' with its last letter removed is 'grape'.
'grape' anagrammed gives 'perga'.
'perga' enclosing 'ol' is 'PERGOLA'.
Can you help me to learn more?
(Other definitions for pergola that I've seen before include "lattice" , "Garden archway" , "Arched garden structure" , "Horizontal trellis" , "Frame for trailing plants" .)