Junk that is put on potato in Scotland (5)
I believe the answer is:
tatie
'potato in scotland' is the definition.
I know nothing about this answer so I can't judge whether this works.
'junk that is put on' is the wordplay.
'junk' becomes 'tat' (both can mean rubbish).
'that is' becomes 'ie' (abbreviation for id est, 'that is' in Latin).
'put on' says to put letters next to each other (some letters go on or after others).
'tat'+'ie'='TATIE'
Can you help me to learn more?
(Another definition for tatie that I've seen is " spud".)