Fighting the heat with balcony plants - urban greening in Postgasse
Summarised for you:
In Bern, prolonged heatwaves and intense rainfall are no longer exceptions. In recent years, we have witnessed these effects of climate change in the city. But what solutions are there to tackle this issue? Plant biologist Matthias Erb gives us an insight into a project launched by the University of Bern that aims to combat the heat in cities and explains what each of us can do to help.
Cramped cities - hot summers
More and more people are living in cities. Due to the high consumption of resources and the considerable generation of waste and greenhouse gas emissions, cities have a major impact on environmental problems. However, they are not only significant polluters, but also suffer from climate change. The effects of climate change were also felt in the city of Bern this summer: although we enjoyed swimming in the River Aare in October, it was still associated with a sour aftertaste. Swimming in the Aare in October? That's somehow not normal. While we joined the queue in front of the Aarestägli in the hottest months, the streets of Bern's old town remained comparatively empty. Why is that? The narrow buildings in cities retain the heat, which means that city dwellers are more exposed - even in Postgasse.
A research project at the university is looking for solutions to keep the summer in Bern's Postgasse bearable for residents. Since May 2023, an interdisciplinary project group has been greening the Altstadtgasse in collaboration with residents in order to counteract climate change. The University of Bern spin-off company Boumwhich has developed a potting system with fully automatic irrigation, is involved in the project. Matthias Erb is the initiator of the project in Postgasse and also plays a key role at Boum. The UniBE Foundation specifically promotes research that prioritises sustainability and innovation. That's why we met Matthias Erb today at Boum's office in Länggasse to find out what has happened in Postgasse and what it looks like today.
Interview with Matthias Erb
UniBE Foundation: Mr Erb, you are significantly involved in the greening project in Postgasse. Why are cities in particular interesting in view of climate change?
55% of the world's population already lives in cities. In the future, almost all of us will be urban. Cities are incredibly fascinating and efficient systems, but they also have huge sustainability problems. They heat up twice as fast as rural areas. They are also poor in nature and the quality of life for city dwellers is often relatively low.
What is the vision behind the project?
By bringing plants into the city, we are solving several problems at the same time. Plants have a cooling effect on the environment and provide the basis of life for pollinators, birds and insects. We humans also benefit from them. It has been scientifically proven that plants reduce stress, make us healthier and happier. That is why the vision is that the cities of the future should be much closer to nature, which in turn directly increases the quality of life and sustainability of these spaces and nature.
Boum - the smart planting system for balconies and patios with automatic irrigation, sustainable soil and natural plant communities. Nicole Stadelmann, Wirz-Tanner Immobilien/Boum AG
What role does Boum play in this project?
Boum shares this vision. Boum is a spin-off of the University of Bern, which we founded with the idea of creating a planting system that would enable everyone to successfully grow and enjoy plants at home.
"Cities are incredibly fascinating and efficient systems, but they also have huge sustainability problems."
Matthias Erb
If we manage to bring such a system to people with Boum, then we will also make cities greener by enabling people in urban areas to green balconies, terraces and entrances. This naturally lends itself to collaboration with the research project. Boum serves as a vehicle to facilitate the transformation.
What motivated you to take on this challenge?
Doing something for the green cities of the future grabbed me because it is an important challenge: it is very topical and will be even more important in the future than it is today. It is my attempt and my intention to make a positive difference in the world.
Why in Postgasse of all places?
Postgasse is a very interesting street, but also a challenging one. It is almost completely sealed. Accordingly, it is incredibly hot. It is also a listed building and densely populated. New buildings can be equipped with green flat roofs or façade greening, but very little has yet been tried out in terms of greening the city centre, which cannot be changed. The greening of Postgasse was therefore an exciting challenge.
How did the people in Postgasse react to this project?
They were very enthusiastic. The city was also in favour of the project. The planting day at the start of the project, which was attended by various economic partners, was a special experience that gave us a lot of energy. It was a great day and many people came.
The project was launched a year ago. What does Postgasse look like today?
The alley is much greener. The people who worked on the project have also contributed to this change. You can see this when you walk along Postgasse today.
What successes can you look back on?
The greening has had some remarkable consequences. In a survey of residents, it emerged that 80% had significantly improved their quality of life. There were also many observations of nature. A large proportion of the population would like the project to continue and have also spoken out in favour of further active participation. We also noticed that individual areas of the alleyway became cooler. However, significantly more greenery would be needed to cool the entire alleyway. It certainly had a positive impact on the overall atmosphere in the alley.
What are the hurdles?
It was certainly important to bear in mind that an alley is both a private and a public space, which is why many different interests have to be taken into account. We had to clarify the project with the event managers and the civil engineering department and look at our room for manoeuvre. However, as everyone agreed that the project was a good thing, it went relatively well. Plants are a good thing - I think everyone agrees on that.
What's next for the project?
The project will continue for at least another year. During this time, we would like to
of greening and long-term effects.
How did the project in Postgasse affect Boum in concrete terms?
The project has certainly helped us gain more visibility to the outside world. The press is interested in such projects. The great thing is that the project combines university research with partnerships from the business world and the public. In this way, we are working together with local residents on a shared vision.
The aim of the project is to green urban spaces. What can each of us do to create a greener space and make a contribution?
The easiest thing to do is to green your own room: everyone has at least one window sill. There's nothing stopping us from greening it. By doing this, we are doing something for ourselves, but also for sustainability. There are also other opportunities, such as getting involved in a neighbourhood association or at a political level. Supporting research at the university and the like is also very important. This is probably where we have the greatest leverage, because this is where solutions are developed that have global potential.
"Supporting university research is very important. This is where solutions are developed that have global potential."
Matthias Erb
Hopeful for the future
An hour later: We say goodbye to Matthias Erb and his team, who are preparing for the spring season in the office. He shows us on site how the Boum system can also be used indoors.
works. Automatic irrigation enables houseplants to grow optimally with minimal effort. The visit to Matthias Erb allows us to look optimistically into a greener urban future despite the upcoming climatic challenges.
Prof Dr Matthias Erb is Professor of Biotic Interactions, Director of the interfaculty scientific cooperation One Health and Co-Director of the Institute of Plant Sciences at the University of Bern. He has received several awards for his research on interactions between plants and their environment. He is also co-founder of the spin-off company Boum, which was launched in 2021.
TO BOUM
Boum is a spin-off of the University of Bern founded in 2021. Using an interdisciplinary, scientific approach, it has developed a user-friendly potting system that is fuelled by ecological and technological knowledge. Using by-products from Swiss forestry and agriculture, the pots contain a substrate that has been developed for irrigation. Irrigation is fully automatic and solar-controlled.
ABOUT THE PROJECT
The interdisciplinary research project was launched on 6 May 2023 in the Postgasse in the old town of Bern. The aim of the project is to find out to what extent sustainability problems in urban areas can be tackled through participatory greening. The alley was planted for the first time in the summer with various scientific, economic and cultural partners as well as local residents. In addition, the effects of the plants on the urban climate and the neighbourhood residents were observed and measured.