Fading melody in gardening section (5)
I believe the answer is:
dying
'fading' is the definition.
(I've seen this in another clue)
'melody in gardening section' is the wordplay.
'section' indicates the answer is hidden within the clue.
'DYING' can be found hidden inside 'melody in gardening'.
(Other definitions for dying that I've seen before include "Passing away" , "Starting to stop!" , "Moribund" , "Ceasing to function" , "On the way out" .)