As this is a cleptoparasitic species, all flower visits will be for nectar only.
Known nectar sources include: Thymus pulegioides (Lamiaceae); Cirsium arvense, Hieracium pilosella and Hieracium umbellatum (Asteraceae) (Westrich, 1989; 2018).
Celary (1990) lists Thymus sp. (Lamiaceae) as a nectar source in Poland