Nice sea colour, one might say, appearing first in rose? (7)
I believe the answer is:
bloomer
'rose?' is the definition.
(I've seen this before)
'nice sea colour one might say appearing first' is the wordplay.
I cannot really understand how this works, but
'sea' could be 'mer' (I have seen 'French sea ' mean 'mer' so perhaps 'sea' could also mean 'mer') and 'mer' is found in the answer.
'one' could be 'o' (I've seen this in other clues) and 'o' is located in the answer.
This explanation may well be incorrect...
'in' is the link.
Can you help me to learn more?
(Other definitions for bloomer that I've seen before include "Stupid mistake" , "made by a baker" , "A slangy blunder or flower in blossom" , "Something from the baker" , "Big mistake" .)