Presumed to be broadly polylectic.
Flowers visted include:Vaccinium myrtillus (Ericaceae), Saxifraga aizoides (Saxifragaceae).
Monsevicius (2004) lists the following forage plants in Lithuania: Calluna vulgaris (Ericaceae); Potentilla (=Comarum) palustre (Rosaceae); Salix sp. (Salicaceae); Melampyrum pratense (Scrophulariaceae); Taraxacum officinale agg.(Asteraceae).
Bossert (2014) reports foraging at Rhododendron ferrugineum (Ericaceae) in the Austrian Tyrol. The specimen was positively be determined as Bombus cryptarum with the analyses of the nucleotide sequence of the COI gene
Anagnostopoulos (2009) reports a worker foraging at Echium (Boraginaceae) flowers in northern Greece. The identity was revealed by a mitochondrial DNA RFLP analysis of the CO1 gene.