Hothouse flower (6)
I believe the answer is:
orchid
'hothouse flower' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for orchid that I've seen before include "Expensive, perfumed flower" , "Family of flowers with unusual shapes and beautiful colours" , "Much sought-after family of plants" , "Highly prized flower" , "Varied much prized flower" .)