As this is a cleptoparasitic species, all flower visits will be for nectar only.
Flowers visited In Devon, G.M. Spooner (pers. comm.) has seen males flying to the flowers of Geranium sanguineum (Geraniaceae) and Sonchus (Asteraceae) In the same locality, S.P.M. Roberts noted a male visiting an Anthyllis vulneraria (Fabaceae) flower (pers. comm.).