1 A total of 33 nests of Xylocopa augusti was studied during two consecutive seasons. 2 Nesting behaviour and floral resources used by the large carpenter bee X. augustiLepeletier de Saint Fargeau were studied during the brood production season in an urban area in Argentina. 3 Biological information about nesting aspects inside and outside the nest was considered, paying particular attention to year-long activity, foraging flights throughout the day for nectar and pollen collection, nectar dehydration, oviposition, and pollen preference. 4 In the study area, X. augusti shows an univoltine life cycle, with a peak of nesting between October and December, which coincides with the greatest blooming period of the surrounding flora. 5 From 36 analyzed larval provision samples, 18 pollen types were identified, most of them belonging to ornamental trees or shrubs. Pollen from Eucalyptus-Myrceugenia glaucescens (Cambess.) D. Legrand and Kausel (Myrtaceae), Solanum sp.-Cyphomandra betacea (Cav.) Sendtn. (Solanaceae) and Erythrina crista-galli L. (Fabaceae) was dominant. 6 The ability to obtain pollen from poricidal anthers such as those of Solanum indicate the potential of X. augusti to be an excellent managed pollinator and a good candidate for pollinating Solanaceae, such as Solanum lycopersicum 'tomato' and Solanum melongena 'eggplant', which are economically important crops in this region.