Poncey ex-oilman returned holding flower (5)
I believe the answer is:
oxeye
'flower' is the definition.
(oxeye matches up with the definition flower)
'poncey ex-oilman returned holding' is the wordplay.
'holding' indicates the answer is hidden within the clue.
'returned' says the letters should be written backwards.
'eyexo' can be found hidden inside 'poncey ex oilman'.
'eyexo' backwards is 'OXEYE'.
(Other definitions for oxeye that I've seen before include "Wild chrysanthemum" , "Daisy plant" , "Kind of daisy" , "Flower; _ daisy" , "Flowering herb" .)