The aim of the study was to investigate the mechanisms of tolerance to Cd, Pb and Zn excess stress in Dianthus carthusianorum, one of the dominant species colonizing an old Zn-Pb waste heap in Bolesław near Olkusz, Southern Poland. Two ecotypes of D. carthusianorum, one growing on the waste heap (calamine ecotype) and the other on unpolluted soil near Lublin (control ecotype) were analysed to identify their morphological and physiological traits as well as genetic markers. Significant phenotypic and genetic variability exists between Dianthus carthusianorum ecotypes originating from waste deposits and non-polluted areas. The calamine ecotype showed higher metal tolerance; however, the mechanisms of this tolerance remain to be elucidated. Our results do not support the important role of glutathione, phytochelatins or organic acids in the enhanced tolerance to metals of the waste heap ecotype.