Local government/municipality

The Productive Backyards Program is led by the NGO Granitos de Paz with the goal of promoting food security and income generation for vulnerable families in Cartagena. The program supports the creation of green gardens in household yards, provide technical training in planting, plant care, and supplies, as well as guidance and support for the creation of productive gardens, it also supports the commercialization of crops, fostering social cohesion within homes and positively impacting their environmental surroundings, nutrition, and health (ref 2, 3). A productive backyard is a small plot of land dedicated to growing vegetables for the family's daily consumption, providing fresh, healthy, and nutritious food. Family labour is utilised, offering both economic and nutritional benefits. This activity helps reduce malnutrition, improve the environment, and enable the commercialisation of organic products by making use of household yards (ref 6).
The program is led by the NGO and occasionally receives support from the mayor's office. The mayor's office has provided kits to the families with gardening tools, a watering can, mesh for enclosures, and seeds for 12 species, including tomatoes, sweet peppers, eggplants, bell peppers, Swiss chard, cabbage, and other vegetables. In addition to these supplies, families received training in entrepreneurship and business ideas for marketing their products, self-consumption, and all related concepts aimed at increasing production (ref 1 and 2). Currently, the program counts with 450 backyards in different neighbourhoods of Cartagena (ref 1).

In January 2024, the municipality of Cagliari inaugurated three new green areas in the city, adding five and a half hectares of green spaces for residents to enjoy. These areas are located between Keplero, Avicenna, and Parigi streets, not far from the city center (Refs. 1 & 2).
The primary goal of this initiative is to mitigate the effects of climate change, particularly rising temperatures. The green areas are designed to reduce the city's heat island effect and contribute to carbon sequestration. The planting of new trees will also help maintain ecosystems and improve environmental conditions in targeted areas . Special attention was given to soil quality, with most projects incorporating walkways equipped with drainage systems (Refs. 1, 2, & 4). Additionally, the new infrastructure aims to foster social engagement and attract more citizens, who will benefit from these improvements. (Refs. 1 & 2).
This initiative is also expected to boost the local economy by encouraging the development of small complementary services (Ref. 3). It is part of a larger municipal project co-funded by the EU.

This project aimed to create an urban forest that will grow within Dublin’s Darndale Park, which is popular among students and sports clubs. The objective is to offer the community a green area where they can gather, appreciate nature, and enhance their knowledge about it. The new forest will act as a windbreak for the nearby fishing pond and aims to address challenges related to heatwaves that endanger the lives of young and elderly people. To foster a sense of inclusion and unity, the forest is designed in a doughnut shape, consisting of 3,000 native species like oaks, birch, willow, and hazel, with the trees forming the outer ring (1, 2). This urban forestation initiative is a component of the Uforest project, which is funded by the European Commission and supported by Etifor (environmental consulting company established within the Department of Land, Environment, Agriculture and Forestry of the University of Padua) and Ersaf (an instrumental body of the Lombardy Region) . The Uforest project seeks to enhance Europe's innovation capacity by fostering collaboration among universities, cities, and businesses to develop a novel approach to urban forestry (1).

Trade winds from the east over the Bay of Fort-de-France increase agitation at the "Étang Z’Abricots" marina, reducing user comfort and raising maintenance costs for port equipment and vessels. Climate change worsen these problems, increasing the risks of coastline erosion, extreme weather events, and rising sea levels, which may diminish the protective effect of "Pointe des Sables," leaving the marina more exposed to the winds (Ref 1; 2).

The Z’AB project aims to address these challenges by creating a protective barrier for the port by using mangroves. This involves installing lightweight, reversible devices to elevate the sea floor and accumulate sediments, encouraging the natural colonization of mangroves south of Pointe des Sables. Natural colonization refers to the growth of mangroves through processes like seed dispersal and sediment buildup. Once established, the mangrove will act as a natural buffer, protecting the marina from rough seas and adapting to rising sea levels. The project also includes educational efforts to raise awareness about the importance of mangroves for the region’s environmental issues and biodiversity (Ref 1).

Although the Z’AB project has been in planning since 2018, in 2021, a separate project to extend the marina, costing 7 million euros, was approved by the water park authorities (Ref 5). The extension will add 77 new vessel spaces (Ref 7), but it threatens portions of the mangrove and a strictly protected coral species, Oculina Diffusa, found in the area (Ref 6, p.17). While the marina extension project aims to offset the loss of coral and mangrove with various solutions, "Projet Z'AB" is not explicitly mentioned as a compensation mechanism (Ref 6, p.24). However, stakeholders involved in Projet Z'AB are also participating in the development of the marina extension (Ref 6). It remains unclear to what extent Projet Z'AB will be used to mitigate the environmental impact of the extension.

The himmelbeet is an intercultural, inclusive community garden in Berlin that has been inviting people to garden and harvest their own produce since 2013. The garden offers around 200 raised beds that are communal and can be rented by neighbors, individuals and institutions (Ref. 1; Ref. 3). The project aims to familiarize children and adults with ecology, sustainability and healthy eating and to offer space for social exchange and education, while being inclusive to people with different (dis)abilities and backgrounds (Ref. 2; Ref. 6). The design and implementation of environmental education workshops are a vital part of the work. (Ref. 1; Ref. 6) With its own café and vegetable production, himmelbeet is strongly oriented towards the principles of the economy for the common good. The garden team also looks after other gardens in the city - on behalf of educational institutions, social institutions, housing associations and neighborhoods. (Ref. 1; Ref. 6)
Originally located in Ruheplatzstrasse, the garden moved in 2021 to Gartenstrasse, because of land disputes with the providing land owners and the demand of the space for other social projects. (Ref. 8; Ref. 11)

Iasi has limited access to green-blue open spaces and fails to meet national and European standards for per capita green space and proximity to larger green areas. Additionally, the city experiences significant fragmentation in its green spaces. To address these issues, the municipality of Iasi launched a project in 2020 to restore a vacant and degraded area, transforming it into a park. Funded by European resources, the project aims to rehabilitate the neglected land by constructing a green park and introducing local vegetation. The primary goal is to provide a leisure and relaxation space for local citizens and visitors while improving the quality of the surrounding air by converting much of the terrain into green space. The vacant land is situated in the historic Ticau neighborhood, which has been affected by municipal neglect, characterized by poor infrastructure and limited connectivity to the city's main areas. Furthermore, the project aims to reduce the heat island effect by creating green oases in a city marked by many “hard surfaces,” such as paved areas, which contribute to this phenomenon expected to intensify in the coming years. Originally scheduled for completion by the end of 2022, the project has been delayed due to a lack of funds and is now expected to be finished by the end of 2024 (Refs 1, 2, 3, 4, 6, 7, 11).

Lima Verde is one of the pillars of the metropolitan mayor's government plan and is supported by SERPAR. It aims to reforest hillsides, hills, and central berms of metropolitan and local roads, as well as public recreational spaces, to create urban lungs that generate oxygen and scenic beauty for the benefit of the health of all residents (Ref 1, 3). Its goal is to plant one million trees in four years (2022 - 2026) in different parts of North, East and South Lima (Ref 3, 5, 6). This project is being carried out to respond to the increasing problem of urban heat islands that are being generated, especially in the most vulnerable districts where there is no shade due to a shortage of trees (Ref 1, 4). It is therefore focused on areas where the environmental quality is low, where the pollution is high and where there is more danger of higher temperatures (Ref 1, 7).
This programme aims to include youth volunteers, district municipalities, educational institutions, grassroots social organisations, neighbourhood leaders, residents and other entities that favour environmental conservation (Ref 1, 2, 3, 5).

The Republic Services Garden is a one-acre garden created and located in Hance Park, a large urban park located in downtown Phoenix, Arizona. As part of the larger revitalization of the park, the garden was created to showcase native desert plants, recycled materials, and shaded seating, serving as a model for eco-friendly urban landscaping. Its key goals are to enhance the park's appeal, create a welcoming community space, and demonstrate the potential of sustainable design in cities. By blending nature with urban infrastructure, the garden helps mitigate the urban heat island effect, addresses water scarcity, and supports habitat restoration. The project is a collaboration between the City of Phoenix and the Phoenix Parks and Recreation Department, with financial backing from Republic Services, the second-largest waste disposal company in the U.S. (Refs. 1, 5, 7, 12, 15).

Trénelle-Citron, located north of downtown Fort-de-France and separated by the city bypass, La Rocade, was originally established in the 1940s by Black Martinicans migrating from rural areas. Today, the neighborhood faces significant economic and social challenges. In 2016, young residents from the neighborhood alongside a local NGO launched a grassroots initiative to improve their community. They transformed a former municipal quarry, which had deteriorated into an informal dump, into a thriving shared urban garden, benefiting the local population. This project, based on traditional ecological gardening techniques and the cultivation of native crops, aimed to revitalize Trénelle-Citron—a densely populated area grappling with social exclusion, a shortage of green spaces, and limited economic opportunities for its youth (Ref 2).

The garden, developed on municipal land with guidance from the Ypiranga Martinique NGO, support from the local school, and collaboration from various stakeholders, now plays a vital role in the area. It raises awareness about agroecology, offers socioeconomic opportunities, promotes healthier lifestyles, and fosters social connections among residents. Spanning approximately 1,000 m², the site includes an office, a covered area, tool storage containers, market garden plots, a composting area, and a chicken coop managed by a local resident (Ref 7). In Martinique, such shared urban gardens are increasingly seen as important tools for sustainable development (Ref 5).

The Africatown Heritage House Bioswale is a gently sloping green space with multiple functions which include catchment of runoff water and filtration of pollution in the runoff water (Ref 2), erosion control (Ref 2), and creation of habitat for biodiversity (Ref 1). It also has an educational purpose for students and the local community (Ref 2) and contributes to overall beautification (Ref 5).
The Bioswale was built by Birmingham-Southern College’s Environmental Center (Ref 6) and developed through the collaboration between the Mobile County Commission, the Mobile Area Lodging Association, Mobile County Training School, Mobile County Training School Alumni Association, and the National Academies of Science (NAS) Gulf Research Program (Ref 2). The project aims to address heavy rainwater management (Ref 5) and drainage issues (Ref 3).