Can you elaborate what you mean by “real plant”? The EnergyPlus Material:RoofVegetation models evapotranspiration from the vegetation if that’s what you are asking. We’re in the process of adding native support for this material in the LBT plugin but, for now, you can add it via add_str_, an OpenStudio Measure, or with some post-processing of the OSM like you see here.