Bedcover has colour that is turning blue (9)
I believe the answer is:
eiderdown
'bedcover' is the definition.
(I've seen this before)
'colour that is turning blue' is the wordplay.
'colour' becomes 'red' (red is a kind of colour).
'that is' becomes 'ie' (synonyms).
'turning' says the letters should be written backwards.
'blue' becomes 'down' (I've seen this before).
'red'+'ie'='redie'
'redie' backwards is 'eider'.
'eider'+'down'='EIDERDOWN'
'has' acts as a link.
(Other definitions for eiderdown that I've seen before include "Feather quilt" , "I wondered about this warm bed covering" , "cover when retired" , "What might keep one warm" , "Warm bed cover" .)