Plant requiring poor drainage (8)
I believe the answer is:
gardenia
'plant' is the definition.
The answer is an example.
'poor drainage' is the wordplay.
'poor' indicates anagramming the letters.
'drainage' with letters rearranged gives 'GARDENIA'.
'requiring' acts as a link.
(Other definitions for gardenia that I've seen before include "Bad drainage can produce a fragrant flower" , "Fragrant tree or shrub" , "Fragrant shrub, red again (anag.)" , "Evergreen" , "Drainage for shrub with white or yellow flowers" .)