Our research aims to evaluate the effect of bunch load variation per unit area on The aim of this study was to examine the effect of different concentrations of heavy metals Pb and Cd on bioavailability in five plant species: nettle (Urtica dioica L.), spelt/dinkel wheat (Triticum spelta L.), spinach (Spinacea oleracea L.), phacelia (Phacelia tanacetifolia Benth.) and buckwheat (Fagopyrum esculentum Moench). These plant species were sown in containers with substrates contaminated with three different concentrations of Pb and Cd. After removal of the crop,the concentration of these metals was examined in the roots and aboveground organs of the plants. The results showed that with increasing concentration of Pb and Cd in the substrate, their concentration in plants increases, except in spelt where the highest concentration of Pb was recorded in the root of spelt grown on the substrate with the lowest concentration of Pb. The results of phytotranslocation potential showed that buckwheat is a suitable plant species for phytoextraction of both Pb and Cd with all three substrate variants, that is at all tested concentrations of both heavy metals.