Plant transported in a car (6)
I believe the answer is:
arnica
'plant' is the definition.
(arnica is a kind of plant)
'transported in a car' is the wordplay.
'transported' indicates an anagram.
'in'+'a'+'car'='inacar'
'inacar' is an anagram of 'ARNICA'.
(Other definitions for arnica that I've seen before include "Application" , "Herbal remedy for bruising" , "Salve" , "Herbal ointment used on bruises" , "Herb used for treating bruises" .)