BBC Earth newsletter
BBC Earth delivered direct to your inbox
Sign up to receive news, updates and exclusives from BBC Earth and related content from BBC Studios by email.
How do you turn a city green? Stand back and let the plants in!
From beehives on rooftops to forest channels pulling cool air into city centres, innovative ideas are bringing nature into urban areas, all around the world. Here are six cities that have found ways to incorporate greenery into their cityscapes – to the benefit of their populations and the environment.
A living wall is how the city of Liverpool has made room for nature in its busy city centre. Strapped for planting space, it turned the barren concrete exterior of the St John’s Shopping Centre into 65 metres (213 feet) of leafy habitat. Installed in 2020,1 Liverpool’s living wall has been planted with 14,000 evergreens, perfectly situated to help trap some of the pollution generated by the city’s nearby bus station.
In 2021, the next phase of the initiative went into action with the rooftop installation of two bee hives. Each houses 20,000 bees2 and on-site staff have been trained up to become expert stewards of their tiny colleagues. A year later, the city centre’s resident bee population is thriving – so much so that the first honey yield from the hives produced 180 jars. The bees don’t just pollinate the living wall, either – they are active within a five-kilometre (three-mile) radius of their hives, helping the ecology of the wider community.3
In Curitiba, north western Brazil, tree planting is the latest phase in making sure the city is as green as possible. Curitiba has been working towards a sustainable model since the 1970s4 and, challenged with a booming population, city planners made the wellbeing of residents their primary concern. Since then, incorporating natural leisure areas and incentivising recycling has become a key part of city planning.
The government’s afforestation plan has seen the planting of many trees beside roads, in parks, squares and other public areas – 139,000 alone between 2013 and 2016. Smaller native species such as the ipê tree are favoured for roadside planting, while the city’s municipal garden propagates larger trees such as the evergreen conifer araucaria for relocating to larger parks.5
Ten ‘mini-forests’ have also been established, making use of smaller areas where larger plantations are impossible. The area is subject to high precipitation and therefore flooding, so environmentally friendly ways to manage the overflow have also been implemented.6 Previously, concrete canals were used to channel runoff rainwater and these were replaced with areas of public parkland.
Often listed as one of Brazil’s greenest cities, Curitiba now boasts more than 1,000 oases of green space.7Surveys show that a high percentage of its citizens are happy where they live – which shows what can happen when cities prioritise people over cars.8
Singapore is determined to be ‘a city in nature’.9 In February 2021 the city-state announced its ‘Green Plan 2030’ - an ambitious programme to make the city as sustainable and nature-inclusive as possible. Singapore already has over 400 parks and four nature reserves10 – and by 2026 this will increase to 300 hectares, with 200 hectares of skyrise greenery by 2030.
By 2030, it has also pledged to plant a million trees across its territory, and further increase parkland by 50 per cent from its 2020 baseline. The promise is that by 2030, no household should be more than a ten-minute walk from an accessible green space – and these should actively promote the health and wellbeing of all residents.11 One of the first of these parks to open is Jurong Lake Gardens, which features Clusia Cove, a threehectare water playground designed to mimic tidal patterns and coastal shores.12 As children play, they can also learn how the water is filtered, cleaned, and recycled naturally through a biotope of aquatic plants, including Hanguana malayanum.13
The Turkish city of Izmir is hoping to reduce pollution with the Mavisehir Peynircioglu Stream Ecological Corridor, a 26,500 m² (285,000 ft²) green ribbon of carbonconsuming vegetation. Opened in October 2020, an additional 1,150 trees and 250,000 bushes have been planted in the area – all species appropriate for the Mediterranean climate.14 The project leaders estimate that activity by pollinators is up by 45 per cent as a result.15
Urban greening doesn’t have to be all or nothing, though. Smaller projects can also help with carbon sequestration and encourage residents to engage with nature. To this end, Izmir has introduced a number of ‘parklets’ around the city – tiny oases offering places for residents to sit amid containers of plants that help reduce the ‘heat island’ effect created by grouped buildings. Taking up far less space (and budget) than a full-scale project, Izmir’s pocket-sized parks are a model for other cities looking for practical ways to introduce nature into urban areas.16
In South Korea, Seoul has planted a forest in a bid to lower city temperatures by 3 to 7°C17. It’s officially a megacity, the designation given to a conurbation with a population of over ten million people. In fact, when including its greater metropolitan area, Seoul houses around 25.6 million, making it one of the most heavily populated cities in the world.18
In 2018, northeast Asia experienced an extreme heatwave – the hottest on record.19 Temperatures soared to almost 40°C20 and two years later, in an effort to counteract further such events, city officials unveiled plans for a new park, named the ‘Forest of Winds'.21 Designed to bring cooling air directly into the city – and also trap polluting particulates and fine dust – the forest was planted with species such as pine trees, maples, wild cherry, and oak. Work on the park was scheduled between November 2020 and the end of 2021, with the Forest of Winds opening in 2022.22
The High Line on the West side of Manhattan is a 2 kilometre (1.45 miles) long wheelchair-accessible public park, built along the remains of an elevated section of disused railway line.23 It closed in the early 1980s and faced demolition before residents banded together to form Friends of the High Line, wanting to put the site to good use. 24
A design competition in 2003 generated interest and ideas for what to do with the space. Perhaps rather sadly, a mid-city rollercoaster was considered impractical – but the idea of an above-street level garden struck a chord. And so the High Line opened in stages from 2009 to 2019, and is now a city greenway featuring over 150,000 flowers, shrubs and trees. 25
Engagement with the public is a huge part of the project’s success. Although administered by the NYC Department for Parks & Recreation, the High Line is maintained and operated by enthusiastic volunteers.26 It’s considered by many to be a blueprint for other cities seeking innovative ways to introduce green space into their urban landscape – Washington D.C is hoping to follow the project’s example with their 11th Street Bridge Park.27
These projects from all around the globe show just how possible it is to incorporate nature into every cityscape. Some of these ventures are large scale, while others have a far more localised impact – but all are innovative and inspirational ways to give the whole planet a helping hand, even in the most urban of environments.
This article was commissioned as part of 'Our Green Planet'. This is a digital initiative, from BBC Earth in association with The Moondance Foundation, to raise awareness for the beauty and fragility of our planet’s green ecosystems. Discover more here. #OurGreenPlanet.
Featured image © Artem Vorobiev | Getty Images
1. Liverpool’s Living Wall, 2. City centre beehives, 3. Bee activity, 4. Curitiba’s sustainability, 5. Afforestation plan, 6. Flood management in Curitiba, 7. Green space in Curitiba, 8. People over cars 9. Singapore, a City in Nature, 10. Singapore’s parks 11. Singapore’s accessible parkland 12. Jurong Lake Gardens, 13. Clusia Cove 14. Mavisehir Peynircioglu Stream Ecological Corridor 15. Increased pollination activity (in Turkish), 16. Izmir’s Pocket Parks 17. Seoul’s drop in temperatures 18. City population, 19. Asia’s 2018 heatwave 20. Recordbreaking city heat 21. Forest of Winds, 22. Forest of Winds timetable 23. The High Line, 24. History of the High Line, 25. Plants on the High Line, 26. The High Line’s Volunteers, 27. 11th Street Bridge Park