Shelves that you might put in wardrobe (9)
I believe the answer is:
mothballs
This clue is a double definition.
'shelves' is the first definition.
(both can mean 'postpones')
'that you might put in wardrobe' is the second definition.
(mothballs protect clothes from moths)
(Other definitions for mothballs that I've seen before include "Camphor spheres" , "Indefinitely postpones" , "Postpones work" , "stores?" , "Deterrent" .)