The main aim of the study was to evaluate the diversity of herbaceous plants cover developing in the soda waste dumps in Krakow and to discuss importance of postindustrial sites for maintaining the biotic diversity. The soda waste dumps were reclaimed by covering with a topsoil, sowed with grass mixture and left without further treatment. In the investigated area 132 plots were laid out on which 133 species of herbaceous plants were identified. Species diversity on individual plots (alpha diversity) was relatively low (average Shannon-Wiener index 1.79), but the plots (beta diversity) differed considerably in species composition (the van der Maarel’s coefficient in 87% cases was less than 0.4). The species occurring on the dumps were typical for many different plant communities, but meadow species and ruderal species predominated. The analysis of Ellenberg indicator values showed the highest variation for the fertility index N. Species dominating the soda waste dumps are those usually found in moderately dry and dry habitats and with neutral soil pH. The reclamation method in which a topsoil layer of low thickness was used prevented succession towards forest communities on the soda waste dumps. Because of this, non-forest communities, that are generally richer in species, can develop. The main threat to species diversity is the development of expansive species, especially the wood small-reed.

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