A bivoltine species: flying from the end of March to late May or June, and again from June to mid September. In Bedfordshire the first brood fails to appear in some localities in some years (Chambers, 1949). According to R.C.L. Perkins (1919g) it is not certain whether it has a special single-brooded race, which appears between the two others.
Parasites: Its nest can be parasitized by the kleptoparasitic bee, Nomada rhenana (Stöckhert 1933, Popov 1967a).