A polylectic species. Amiet et al. (2010) suggest that it will collect pollen from a range of different plant families, a view supported by Praz et al. (2019) who state that the species is known to collect pollen from 12 plant families.
Praz et al. (2019) state that flowers of the Campanulaceae, Helianthemum (Cistaceae) and Caryophyllaceae were the most important pollen hosts contributing 73.4% to the total pollen volume, whereas the pollen of all other taxa was represented by less than 10% each. Additional forage sources include Euphrasia-type (Orobanchaceae); Asteraceae (Cichoroidea, Asteroidea); Ranunculaceae; Veronica (Plantaginaceae); Geranium (Geraniaceae); Crassulaceae; Hypericum (Clusiaceae); Lamiaceae (Nepetoidea); Rosaceae.