Artist capturing hearts with a flower (6)
I believe the answer is:
dahlia
'flower' is the definition.
(dahlia is a kind of flower)
'artist capturing hearts with a' is the wordplay.
'artist' becomes 'dali' (I've seen this before).
'capturing' means one lot of letters goes inside another.
'hearts' becomes 'h' (abbreviation used in card games e.g. bridge**).
'with' means one lot of letters go next to another.
'dali' enclosing 'h' is 'dahli'.
'dahli'+'a'='DAHLIA'
(Other definitions for dahlia that I've seen before include "Brightly coloured garden flower with tuberous roots" , "Lia had this strange flower" , "Tuberous garden plant" , "Garden plant with large brightly-coloured flowers" , "Aid Hal (anag) - flower with showy heads" .)