Gloomy flower? Hoped lass not wholly distressed (8)
I believe the answer is:
asphodel
'gloomy flower?' is the definition.
(underworld flower in Greek myth)
'hoped lass not wholly distressed' is the wordplay.
'not wholly' means to remove the last letter.
'distressed' indicates an anagram.
'hoped'+'lass'='hopedlass'
'hopedlass' with its final letter removed is 'hopedlas'.
'hopedlas' with letters rearranged gives 'ASPHODEL'.
(Other definitions for asphodel that I've seen before include "Mediterranean plant" , "Old shape (anag) - plant" , "Shop deal (anag.)" , "Elysian plant" , "Lily-like plant, the flower of death to ancient Greeks" .)