Modern high-priced artificial plants can look very much like real plants. However, no matter how good the UV protectants are, they will start to look worn and torn as time passes. On the contrary, real plants grow and thrive and will look better and better as the months and years pass; they are alive and developing. Natural plants also bring many secondary benefits to the table that plastics cannot.
Green walls – an old and trusted technology
Sometimes, clients seem to think green walls and green roofs are something new and fancy. This could not be further from the truth. Humanity has used green infrastructure as workhorses for many thousands of years. Archeological finds show that 2000 years ago, green walls were used to cool the houses in the Mediterranean. Those plants also provided economic value as many also produced fruits.
Green infrastructure has been used to cool factories and other buildings in central Europe since long before the Industrial Revolution. This is not new technology. It is more like a temporary glitch and collectively we forgot how useful it is to have nature work for us passively, and essentially for free. Luckily, the glitch has passed, and the importance of green infrastructure is again widely recognized for its positive effect on the urban environment.
Green infrastructure vs. artificial plants
A common misconception is that green infrastructure such as green walls and roofs are only installed because they are attractive. Sure, they are beautiful and can create peaceful refuges that are sorely needed in our urban asphalt jungle, but they are also workhorses that provide essential ecosystem services.
To miss out on these essential services as urban heat islands soar and carbon capture is of the essence is frankly not only irresponsible but can also be economically unfavorable.
Green infrastructure is a good investment
Carbon capture: greenscreen trellis systems allow for plant carbon capture due to carbon assimilation into woody stem biomass. Plastic plants are made from petrochemicals and have a terrible carbon budget.
Energetic savings: green walls and green roofs cool a building not only through simple shading but remove heat from the building as the plants evapotranspire (release water into the air). This is an exceptional cooling engine that most of us have experienced when jumping from hot asphalt to a cool meadow. This cooling leads to building energetic savings as the building gets directly cooled and air conditioning units take in cooler air leading to lower energy use.
Stormwater: since real plants evapotranspire, they remove vast quantities of rainwater that never have to be fed into the sewer system. For green roofs, this can be 30-70% of the annual precipitation depending on the profile and climate. This retention capacity results in lower sewage fees in addition to the money saved through energetic savings.
Biodiversity and mental health: green infrastructure also creates biodiverse biophilic islands that are good for both environment and the human mind. There has been a lot of research conducted that shows that humans feel better in a natural setting. If this argument is insufficient, a lot of money is saved as employees miss fewer workdays and patients can be released earlier from hospitals. We work better and we heal better with green infrastructure.
Pollution capture: green walls are also excellent at pollution capture. This is no small feat, as air pollution is the fourth leading global risk factor for death. It has been shown that the greening of external walls reduced harmful PM2.5 and NO2 by 11% to 31% and 7% to 20% respectively.
In summary, plastic plants are outdated, not environmentally friendly, and bring virtually no secondary benefits to the table.
By Dr. Anna Zakrisson