Swedes lie about plant (9)
I believe the answer is:
edelweiss
'plant' is the definition.
(edelweiss is a kind of plant)
'swedes lie about' is the wordplay.
'about' is an anagram indicator.
'swedes'+'lie'='swedeslie'
'swedeslie' with letters rearranged gives 'EDELWEISS'.
(Other definitions for edelweiss that I've seen before include "Alpine flower - "The Sound of Music" song" , "Swedes lie about small white flower in Switzerland" , "White-flowered alpine plant" , "Deep admiration" , "Perennial Alpine plant -- we see lids (anag)" .)