He returned wheat cultivated poorly (5,3,7)
I believe the answer is:
under the weather
'poorly' is the definition.
(thesaurus)
'he returned wheat cultivated' is the wordplay.
'cultivated' indicates anagramming the letters.
'he'+'returned'+'wheat'='hereturnedwheat'
'hereturnedwheat' is an anagram of 'UNDER THE WEATHER'.
(Other definitions for under the weather that I've seen before include "put umbrellas up here?" , "where you have to look for this crossword?" , "Depressed" , "with clouds gathering overhead" , "Seedy" .)