As this is a cleptoparasitic species, all flower visits will be for nectar only.
Flowers visited: A single record: Vincetoxicum officinale (Asclepiadaceae) (Westrich, 1989), a species not native to the United Kingdom.
Celary (1995) and Celary & Wisniowski (2001) list Sinapis arvensis (Brassicaceae) and Antitoxicum officinale (as Vincentoxicum[sic]) hirundaria (Asclepiadaceae); Solidago virgaurea (Asteraceae).
Monsevicius (2004) lists Veronica (Plantaginaceae) and Fragaria vesca (Rosaceae) as a nectar source in Lithuania.