Vertical Forests - Garden trees planted on tower blocks
Green open spaces in cities help improve the quality of life for human residents and also provide habitats for many different species of wildlife. Trees and plants produce oxygen and remove pollutants from our atmosphere.
Unfortunately, space in modern cities is at a premium and while everyone agrees that it is more pleasant and healthy, both physically and mentally, to live amongst green spaces there is not much incentive to build urban parks and conservation areas as they are not profitable.
Italian architect Stefano Boeri is leading the way with an innovative solution: Vertical Forests.
Trees and shrubs are planted on the exterior of buildings to help reduce smog and also produce oxygen. They also help to regulate temperatures inside the building as they act as insulation, keeping buildings cool in summer and reducing heat loss in the winter. Another benefit is the reduction of noise pollution particularly useful in noisy city areas, reducing the amount of noise residents hear from busy traffic and other general city noise. These vertical forests provide a habitat for birds and insects and so encourage nature back into what would otherwise be grey and soulless tower blocks.
Because they are planted in ascending vertical layers they do not take up anywhere near the amount of ground space that the same number of trees planted vertically would. Space in modern cities is at a premium these days and either too expensive to build on or simply unavailable.
The first project, Bosco Verticale, was completed in 2014 in Milan. Consisting of 2 residential tower blocks it uses different types of trees, ground cover plants and shrubbery to form the equivalent of a 10,000 square metre forest in the centre of one of the world's busiest cities. Consisting of 2 towers, 75 metres and 110 metres tall, this inner city forest is made up of 900 trees and more than 20,000 shrubs and ground-cover plants.
The particular species of plant-life used was decided on after lengthy consultation with a team of botanists and horticulturalists. They were consulted to make sure that the trees and plants would be able to thrive.
There is only limited space for tree roots to grow on each balcony, different to trees grown on the ground whose roots can extend down into the earth and spread outwards, and this was why a team of experts was asked to ensure that appropriate species were used.
Nations Catching On
The towers in Milan were inaugurated in 2014 and have proven to be popular with residents, so popular that there is now a vertical forest nearing completion in the city of Lausanne, Switzerland, and plans have recently been confirmed for a new vertical forest to be built in China.
The project in Switzerland consists of a single tower 117 metres tall that is predominantly a residential building but also contains a gym, offices and a restaurant with panoramic views over the city. Planted with hundreds of Cedar trees it is known as "La Tour Du Cedres" (Tower of Cedars)
The latest project to be revealed will be constructed in the Chinese city of Nanjing and will consist of 2 towers that will be home to over 1,100 trees (made up of 250 different species) and more than 2,500 shrubs and plants. China suffers from some of the highest levels of air pollution in the world with densely populated cities and an abundance of industrial air pollution. It is estimated that the towers in Nanjing will absorb enough carbon dioxide to make 60 kilograms of oxygen every day and absorb over 25 tonnes of carbon dioxide each year.
Recognising the need to improve living conditions in cities the Chinese already have plans to build more vertical forests in another 5 cities. The first Chinese project is expected to be completed in 2018 and will be the first such project in Asia.
The idea has caught the attention of city planners worldwide with the first vertical forest in Australia being planned for Brisbane. The concept has captured the imaginations of city planners to such an extent that Stefano Boeri is now working on planning an entire “Forest City.” Instead of 1 or 2 buildings being built in existing cities, the “Forest City” would be a purpose built new city consisting of up to 200 buildings all covered in trees, plants and shrubs. Boeri believes that we could see the first Forest City completed in China as early as the year 2020.
Other Benefits of High Rise and Rooftop Gardens
A way of improving city life for city dwellers, not just residents of the buildings but everyone in the city as they help to improve air quality, house wildlife and also are much more aesthetically pleasing than standard tower blocks. They also allow city dwellers to live closer to nature, something that is usually limited to the decreasing minority who have their own gardens.