Autumn bloom (5)
I believe the answer is:
aster
'autumn bloom' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for aster that I've seen before include "Stare at pretty flower" , "It grows" , "Plant of Michaelmas daisy family" , "Stare oddly at the flower" , "Garden plant" .)