Land not cultivated in stages, we’re told (7)
I believe the answer is:
steppes
'land not cultivated' is the definition.
(steppes are uncultivated flat land)
'stages we're told' is the wordplay.
'stages' becomes 'steps' (both can mean parts of a process).
'we're told' shows a homophone (sound like).
'steps' is a homophone of 'STEPPES'.
'in' is the link.
(Other definitions for steppes that I've seen before include "grassy areas" , "Russian treeless plains" , "Eurasian grasslands" , "Dry grassy plains of Russia" , "Great plains of Russia" .)