New rose variety is European (5)
I believe the answer is:
norse
'is european' is the definition.
(I've seen this before)
'new rose variety' is the wordplay.
'new' becomes 'n' (common abbreviation eg NT for New Testament).
'variety' indicates anagramming the letters.
'rose' anagrammed gives 'orse'.
'n'+'orse'='NORSE'
(Other definitions for norse that I've seen before include "Snore (anag)" , "These men were Vikings" , "Old Scandinavian language" , "Ancient Scandinavian language" , "Viking" .)