For plant dad gets right bargain (7)
I believe the answer is:
parsnip
'for plant' is the definition.
(parsnip is a kind of plant)
'dad gets right bargain' is the wordplay.
'dad' becomes 'pa' (both can mean one's father).
'gets' is a charade indicator (letters next to each other).
'right' becomes 'r' (common abbreviation).
'bargain' becomes 'snip' (slang term for a good deal).
'pa'+'r'+'snip'='PARSNIP'
(Other definitions for parsnip that I've seen before include "Plant with edible white root" , "Type of root veg" , "A white root vegetable" , "food" , "Spar pin (anag) - vegetable" .)