Fertile spots in a desert (5)
I believe the answer is:
oases
'fertile spots in a desert' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for oases that I've seen before include "Fertile tracts in a desert" , "Fertile desert spots" , "Fertile desert places" , "Where there may be dates" , "These sanctuaries" .)