Belowground soil characteristics are recognised as possible key factors in affecting plant species coexistence and community organisation. In this study, soil heterogeneity was generated by the growth of different herbaceous plants under controlled conditions, and thus related to growth and competitive ability of three naturally co-occurring species (Holcus lanatus, Inula viscosa and Pulicaria dysenterica). Soil changes induced by all species caused significant specific effects on the performance of these species and on their competitive hierarchies. Holcus lanatus was the strongest competitor on disturbed soil, but showed a dramatic negative feedback in monoculture. The experimental results are relevant for understanding community ecology and suggest that the investigation of species coexistence should take into account the possible role of plant-soil feedback processes