Talk about a point raised by a nurseryman (7)
I believe the answer is:
parsley
'raised by a nurseryman' is the definition.
I can't tell whether this defines the answer.
'talk about a point' is the wordplay.
'talk' becomes 'parley' (to parley is to talk with an enemy).
'about' means one lot of letters goes inside another.
'a point' becomes 'S' (South).
'parley' going around 's' is 'PARSLEY'.
Can you help me to learn more?
(Other definitions for parsley that I've seen before include "Herbal garnish" , "Herb with either flat or crinkly leaves" , "Green plant" , "Herb (flat-leafed or curly)" , "plant used in cooking" .)