Popular pot plant (8)
I believe the answer is:
geranium
'popular pot plant' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for geranium that I've seen before include "Common garden or house plant" , "Flower confused with pelargonium" , "Cultivated flower often seen in window box" , "Pelargonium (loosely)" , "Herbaceous plant" .)