Amazingly true: roses turned up! (9)
I believe the answer is:
retrousse
'turned up' is the definition.
(retrousse describes an attractively turned up nose)
'amazingly true roses' is the wordplay.
'amazingly' indicates an anagram.
'true'+'roses'='trueroses'
'trueroses' is an anagram of 'RETROUSSE'.
(Other definitions for retrousse that I've seen before include "turned up in Nice" , "(Of noses) upturned" , "Of nose, turned up at tip" .)