Abstract
Green roof units consisted of sedum plants and artificial soil has been popular because of its simple and light structure. The evapotranspiration characteristics is enough complex, however, and it is not discussed yet. We conducted a long term experiment that cleared the amount of evaporation is connected with the amount of solar radiation and the moisture content in the soil under warm climate. In the cold months of the year, the effect of water content was rather weak. We continuously measured the unit without plants after the main experiment and cleared the plants effectively control the speed of evaporation of the soil.