Depressed beauty said to want plant (8)
I believe the answer is:
bluebell
'plant' is the definition.
(bluebell is a kind of plant)
'depressed beauty said' is the wordplay.
'depressed' becomes 'blue' (I've seen this before).
'beauty' becomes 'belle' (I've seen this before).
'said' indicates a 'sounds like' (homophone) clue.
'belle' sounds like 'bell'.
'blue'+'bell'='BLUEBELL'
'to want' acts as a link.
(Other definitions for bluebell that I've seen before include "Wildflower" , "Perennial" , "Spring woodland plant" , "Plant with bell-shaped flowers" , "former dancing girl" .)