American flower planted in European capital city (8)
I believe the answer is:
aberdeen
'city' is the definition.
(Aberdeen is an example)
'american flower planted in european capital' is the wordplay.
'american' becomes 'a' (common abbreviation - e.g. in organisation names).
'flower' becomes 'dee' (River Dee).
'planted in' is an insertion indicator.
'european capital' becomes 'Bern' (capital of Switzerland).
'dee' placed into 'bern' is 'berdeen'.
'a'+'berdeen'='ABERDEEN'
(Other definitions for aberdeen that I've seen before include "somewhere in Scotland" , "Bare need to be in Scottish city, oddly" , "Grampian city and port" , "Scotland's Granite City" , "Scottish East coast city" .)