Elaborated on a ‘crop suitability’ concept, hierarchically arranged functions are combined to appraise the agro-environmental conditions (management, phenology, air temperature, solar radiation, water and nitrogen availability) controlling the establishment and growth of plant species in multi-species grasslands. With these functions, generic crop simulators originally developed to represent vegetation cover as an average plant evolve towards representing explicitly and dynamically the relative abundance of the different species that comprise a grassland community. Novel modelling solutions were obtained by coupling the software component CoSMo (Community Simulation Model), which implements such suitability functions, with two crop simulators of large use worldwide (CropSyst and WOFOST). Results show that these solutions are adequate in simulating the multi-year plant dynamics of Italian and French grassland sites. This occurs because the models predict changes in community plant traits from the traits of individual species (fixed model parameters) and their relative abundances as simulated at daily time steps. With an explicit representation of plant diversity, we aim to better infer the ecosystem services delivered by grassland, which depend on floristic composition. With this ongoing research, we anticipate that better estimates can be obtained of the main provisioning service, i.e. forage production.