Study on Behavior of Some Perennial Flowering Species Used in Vertical Systems for Green Facades in Eastern European Climate

The negative effects of urbanization such as urban overheating, pollution, high population density and so on are being experienced by city inhabitants more than ever, thus motivating a high number of researchers to find viable solutions to mitigate these effects. The present paper aims to identify an assortment of ornamental plants appropriate to be successfully used in various facade covering systems for buildings located in Eastern European countries. For this purpose, throughout a vegetation season, the project's team thoroughly monitored the percentage of survival, the coverage degree, and the behavior (biometric aspects and visual quality) of ten flowering species planted vertically and being oriented towards all four cardinal points. At the same time, the team conducted a thorough monitoring of some parameters of the soil (pH, humidity, and temperature) and of the outside environment (light intensity and temperature). Two experimental structures were built, insulated on the inside and covered at the top with thermal insulating panels, to simulate the same conditions of an insulated and unheated construction. The monitoring results showed that Heuchera x hybrida 'Fire Alarm', Heuchera x hybrida 'Marmalade' and Festuca galuca had a healthy appearance throughout the year, regardless of the cardinal orientation while providing a good coverage of the vertical surface.