Looking back, notice painting showing cover on bed (7)
I believe the answer is:
topsoil
'cover on bed' is the definition.
'topsoil' can be an answer for 'bed' (thesaurus). I'm unsure of the 'cover on' bit.
'looking back notice painting' is the wordplay.
'looking back' says the letters should be written in reverse.
'notice' becomes 'spot' (spot can mean to notice or observe).
'painting' becomes 'oil' (oil painting is a kind of painting).
'spot' written backwards gives 'tops'.
'tops'+'oil'='TOPSOIL'
'showing' acts as a link.
Can you help me to learn more?
(Other definitions for topsoil that I've seen before include "Earth's surface" , "The Good Earth" , "Visible layer of garden" , "surface of earth" , "best part of earth" .)