Being made richer gives Manfred a change of heart (7)
I believe the answer is:
manured
'being made richer gives manfred a change of heart' is the definition.
I can't tell whether this definition defines the answer.
'being made richer gives manfred a change of heart' is the wordplay.
'being' becomes 'man' (human being).
'made richer gives manfred' becomes 'ure' (I can't justify this - if you can you should believe this answer much more).
'a change' becomes 'ado' (ado is a kind of change).
'of heart' says to take the centre (I've seen 'heart of' mean this).
The middle of 'ado' is 'd'.
'man'+'ure'+'d'='MANURED'
Can you help me to learn more?
(Another definition for manured that I've seen is " mucky".)