A rug - mine possibly shows plant (8)
I believe the answer is:
geranium
'plant' is the definition.
(geranium is a plant)
'a rug mine possibly' is the wordplay.
'possibly' indicates an anagram.
'a'+'rug'+'mine'='arugmine'
'arugmine' is an anagram of 'GERANIUM'.
'shows' is the link.
(Other definitions for geranium that I've seen before include "Flower confused with pelargonium" , "Commonly cultivated plant" , "Cultivated flower often seen in window box" , "Popular flower" , "Pelargonium (loosely)" .)