Vacant or abandoned land

Over the past 10 years, Lima's population has grown from 8.2 to 9.6 million people. As the city's urban sprawl and population density have increased, green spaces have been replaced by grey infrastructure. Consequently, it has become challenging to ensure that residents enjoy a good quality of life (1, 2, 3). In December 2019, Lima City Hall launched "Limeños al Bicentenario," an initiative to revitalise the city's public spaces (1, 3). This program seeks to transform public areas through low-cost interventions, based on criteria such as vulnerability, citizen participation, and catalytic potential, among others (3). It also aims to foster social cohesion by involving residents in the maintenance of these newly renovated areas, while improving the city's resilience to climate change (1, 2, 3). Since its inception, the project has reclaimed 17 public spaces, covering an area of 41,000 m² (3). 430 trees have been planted, and the project has benefited from the collaboration of civil society and private sector partners (3). The programme also focuses on addressing climate change. Heat waves, droughts, floods and mass migration are the main climate-related risks affecting the city. In particular, the expansion of grey infrastructure at the expense of green spaces has exacerbated the risk of heat waves, causing temperatures to rise by up to 3.5 °C in certain areas of Lima (3).
One of the projects involved the recovery of public spaces in Teniente Pavia. For many years, the space was used as a public parking lot, and at night it accumulated garbage, there was alcohol consumption, drug use, and other problematic issues. There was no vegetation, benches or infrastructure for recreation. The neighbours, especially children, did not have access to green areas or recreational spaces (5). For this reason, in 2020 the project was initiated to repair sidewalks, plant vegetation, create gardens, and install infrastructure for play, rest, and exercise (3, 4).

The Görömböly European Bee-eater Habitat Protection Project, launched in 2002 in Miskolc-Görömböly, Hungary, is a key conservation initiative dedicated to protecting 26.5 hectares of critical habitat for the highly protected European Bee-eater (Merops apiaster) and the Sand Martin, along with the diverse ecosystems thriving in this area.
The site comprises three unique zones: an abandoned sand quarry, a young acacia woodland, and a quarry lake surrounded by marshlands. The sand quarry’s vertical walls provide nesting sites for 15-40 European Bee-eaters and Sand Martins each year, supporting Red-listed species vital to Hungary’s biodiversity. The acacia woodland serves as a feeding ground, while the quarry lake nurtures a rich aquatic ecosystem, hosting protected species like the European Bitterling fish, amphibians such as Green Toads, and a variety of waterfowl, including Mallards, Little Grebes, and occasionally Kingfishers.
This project not only safeguards these vulnerable species but also fosters community engagement, offering residents the chance to learn about local wildlife and ecosystems. Additionally, the initiative promotes scientific study of the area’s ecological development, contributing valuable insights into species behavior and habitat evolution. With an emphasis on nature education and recreation, the project raises public awareness of environmental conservation.
The Municipality of Miskolc plays a crucial role, having designated the area as a protected site and managing its regulatory enforcement and maintenance.
(Ref.1,2,3)

The Horpaz-Ezareni Park is an initiative driven by civil society, requesting the municipality of Miroslava to construct a natural park adjacent to Lake Ezareni. The aim is to protect its green spaces and aquatic bird species while addressing waste management in the area. The petition also called for more green spaces in line with European standards and sought to tackle the challenges of rapid urbanization in peri-urban areas. It collected hundreds of signatures and targeted an area of 20 hectares.
In response, the municipality agreed to the petition and initially proposed creating a park covering 4 hectares in 2022. This first plan was released to the public for consultation. However, the project has since evolved to encompass the original 20 hectares, plus an additional 2 hectares, with an estimated project cost of 11,000,000 euros and a timeline of 3 years for implementation.
The park's design includes various facilities and amenities aimed at enhancing opportunities for recreation, exercise, and relaxation. Accessible paths for pedestrians and cyclists, as well as a parking lot, are also part of the plan. Additionally, two buildings are proposed for sanitary and administrative purposes, which would manage the projected installations of a lighting system, Wi-Fi, and surveillance cameras.
Environmentally, the project includes plans for managing the lake's banks to remove hydrophilic vegetation that could create an unhealthy environment, along with the construction of two bridges. The wilderness areas will be managed, and dendrological plants will be introduced to improve the ecosystem's quality. Overall, the project aims to increase and regenerate green spaces in the commune, enhancing the quality of life for residents and improving the area's aesthetic appeal. (1-8)

Earthworks Urban Farm, located on Detroit's east side, is a pioneering initiative of the Capuchin Soup Kitchen that integrates sustainable agriculture, social justice, and community development. The Capuchin Soup Kitchen is a religiously affiliated soup kitchen and non-profit organization located in Detroit, Michigan. It was founded by the Capuchin friars to provide food for the poor during the Great Depression and is sponsored by the Capuchin Franciscan Province of St. Joseph. The farm was founded in 1998 by Brother Rick Samyn, and began as a small garden focused on educating local youth about healthy food and its origins. Over time, this modest garden expanded into a 2.5-acre urban farm, including 1.5 certified organic acres—making it Detroit's only certified organic farm.
The farm’s growth included adding a large plot behind its partner, Gleaners Community Food Bank, as well as establishing an apiary with up to 40 hives, a greenhouse for transplant production, a hoop house for year-round crops, and a community orchard. Earthworks' work has evolved along with its physical space, significantly extending its reach.
A wide variety of vegetables are cultivated here without herbicides or pesticides, with harvests distributed to local residents and included in meals at the Capuchin Soup Kitchen, ensuring fresh, nutritious food for those in need. Beyond agriculture, Earthworks serves as a community hub, engaging volunteers, offering educational tours, and supporting thousands of community gardens across Detroit with transplants and expertise.
Committed to evolving its programs, Earthworks has experimented with mobile markets, community-supported agriculture (CSA), and local market stands, demonstrating its dedication to meeting community needs through sustainable practices.
(Ref.1,2)

The Avas Tomato Community Garden, located in a formerly neglected area of the Avas hill of Miskolc, has transformed from an overgrown, rat-infested, and litter-strewn space into a thriving community garden. Just a few years ago, this site was a source of concern for local residents, plagued by issues such as homelessness and illegal dumping. Today, however, it stands as a flourishing green space with fresh garden beds, composting boxes, a pavilion offering shade to gardeners, and a renewed sense of community spirit.
The seeds of the Avas Tomato Community Garden project were planted in the fall of 2014, led by Zsolt Jakab and Ákos Káli-Nagy. The initiative began with the establishment of the "Panelkertész" club, and by 2016, with the support of a local representative, the garden began to take shape. The gardening community that blossomed in the spring of 2017 was built upon the strong relationships within the established Avas neighborhood. Working together, members constructed the garden beds according to a precise schedule and, through frequent discussions, developed a close-knit community. The garden now consists of 20 large and 6 smaller beds, with 18 families actively growing vegetables, herbs, and spices, alongside raspberry and strawberry plants by the fence.
The community has greatly benefited from both the professional support and supply donations provided by the Miskolc Ecological Institute Foundation. Additionally, the Dialóg Association has played a key role in organizing the garden users and fostering collaboration. Initially, Dialóg appointed a coordinator for the garden, but this responsibility has since been handed over to the gardeners themselves. Owned by the Municipality of Miskolc, the Avas Tomato Community Garden continues to thrive as a model of successful urban gardening, uniting people with a shared passion for gardening and a commitment to building a strong, supportive community.
(Ref.1,2,3)

The Green Wall of Tomesti was an initiative launched by the commune of Tomesti to combat air pollution from the nearby city of Iasi, which often drifted into the area (1, 2). The municipality decided to implement this solution after consulting specialists on how to address pollution from the main urban area. It was also integrated into the objectives of their 2014 General Urbanistic Plan, which aimed to transform Tomesti into a "modern, clean, and ecological area" (1, 2, 5). In addition to mitigating air pollution, the forest wall was expected to help lower local air temperatures (1).
The municipality purchased seedlings and planted the trees at the end of 2019, near the D.D. Patranascu school (1-3). While the overall goal was to protect the entire commune and improve the health of Tomesti's residents, particular attention was given to safeguarding the school closest to Iasi (1, 2). Before planting, the organizers called for volunteers to help with the plantation (3). In total, approximately 1,500 trees were planted (linden, acacia, oak and willow), with a space of 1,5 m between each other (2).
The action also follows on a 20-year national plan to increase forest walls to improve the quality of the air in the country (6).

The municipality of Ciudad Juarez, in collaboration with UN-Habitat, has drafted a redevelopment strategy for an area known as "Paso de Oñate." This intervention falls within the broader framework of "Vision Ciudad Juarez 2040." The plan involves constructing a forested green belt along the southern edge of the Rio Grande (/Bravo) in the northwest part of Juarez, bordering the USA.
Currently in the planning stage, the project aims to restore the ecological function of various degraded areas along the Rio Grande, transforming them into a continuous, green, walkable, and recreational space. The strategy includes allowing vegetation to recover, introducing native plant species, and increasing tree cover to rehabilitate unmaintained parks, derelict areas, and degraded riverbanks. These areas will be equipped with new features and integrated with existing parks, schools, and playgrounds. The envisioned green corridor will enhance walking conditions, improve the perception of safety, offer recreational opportunities for all age groups, and deliver valuable ecosystem services such as temperature regulation, improved air quality, and water retention.
In addition to its ecological goals, the project has a historical and geographical dimension. It aims to incorporate cultural heritage elements, such as the monument of the New Citizen, Paso de Oñate, Turtles Park, and the beginning of the Acequia Madre. It will also connect with other green space initiatives, including the Mega Park "El Chamizal" and the "Corredor Cultural," which runs through the city center.
This intervention is being prioritized due to the area's ongoing social and ecological decline. Paso de Oñate is a critical border crossing point, which negatively affects mobility and air quality. The area also suffers from a high concentration of vacant housing, which contributes to the residents' perception of insecurity. (Ref. 1, 2, 3, 4)

A biodiversity park was built on an abandoned plot of land that felt unsafe to local residents. In the future, the plot may eventually be used for the construction of something more permanent. In the meantime, this project seeks to increase safety and access to greenspace while benefiting biodiversity, specifically flowers and insects.
Recycled materials were used to create the structure of the park, places to sit and insect hotels, while trees and a flowering meadow were planted. A mix of annual and perennial flowers was used to promote biodiversity over time. The locals are reported to be happy with the project. Familjebostäder i Göteborg AB, a publicly owned real estate company, conducted the project. [Ref. 1-5]

In 2018, a group of residents from Sector II in the Villa El Salvador district initiated a communal effort to transform an abandoned space into an urban garden (3). This is how Ayllu 21, the first community-based agroecological garden in Villa El Salvador, was born. The project was spearheaded by a group of mostly migrant senior women who decided to dedicate their time and labour to reclaiming a landfill space, to turn it into a productive green area (1). Their philosophy is rooted in the concept of "ayllu," a Quechua word signifying family, collective identity, solidarity, and respect for the environment to foster harmonious coexistence (3).
Today, Ayllu 21 spans 1400 square meters and features 40 plots where agroecological practices are employed (1, 3). The garden aims to become a space for comprehensive development, through promoting environmental awareness, political advocacy, and the fight against gender-based violence in a district that ranks third in the number of violence cases (1).
The vegetables produced are primarily for self-consumption, with any surplus distributed among neighbouring families. If there are any sales, the profits are shared among the members, who work an average of two days per week in the garden (3).
This space seeks to strengthen socialization among women and seniors and foster learning and community-building among neighbours through agriculture. It was initiated with the support of IPES Promotion of Sustainable Development as part of the Sowing in the Desert program (3, 6), and it has received support from a diversity of programmes, such as the framework of the Women United for Food and Environmental Security (MUSA) (1).

Maya’s Farm is a small, CSA (Community Supported Agriculture) sustainable urban farm located in Phoenix, Arizona, where urban development has limited farmland availability. In 2020 alone, Phoenix lost nearly 200 acres of farmland to urban sprawl, putting farms like Maya’s at risk. The farm faced potential closure until the City of Phoenix intervened, providing funding through the Farm Preservation Program, which established the city's first urban agricultural conservation easement. Maya's Farm strives to inspire a local appreciation for sustainable food and to bring renewed value to local food systems.
The farm’s mission is to provide accessible, fresh, locally grown produce to the community while promoting awareness of healthy, sustainable food practices. Through its CSA program, members receive a weekly produce box and have opportunities to come together, honor food traditions, and share stories over locally harvested food. As a CCOF (California Certified Organic Farmers) certified organic farm, Maya’s Farm is committed to organic practices that exclude GMOs, nurture the soil, foster biodiversity, and innovate growing systems. These methods result in healthy soil and cleaner air, contribute to carbon sequestration, and support critical wildlife habitats.
To broaden educational outreach, Maya’s Farm offers several programs that promote sustainable food practices, including its CSA program, an edible classroom series, and a partnership with Arizona State University (ASU). Through this ASU partnership, students gain hands-on experience by participating in daily farm operations.
Building stronger community connections is another cornerstone of Maya's Farm’s work. The farm collaborates with local restaurants, farmers' markets, and community groups to expand its impact. Maya’s Farm, ASU, and Arizona Sustainability Alliance launched an agrivoltaics project with solar-shaded crops. (2, 9, 11, 13, 15)