Research & reports

Olivia G Bassetti, Rebecca A McDonough, Kabindra M Shakya · Environmental Monitoring and Assessment · United States (Philadelphia, Pittsburgh)

A 2023 study that sampled soils from 21 community gardens in Philadelphia city, the Philadelphia suburbs and Pittsburgh city, Pennsylvania, USA, in September–October 2021 and measured seven elements (Pb, Zn, Cu, V, Cd, Ni, As) by ICP-MS. City gardens had higher concentrations than suburban ones. All elements except vanadium fell below Pennsylvania Department of Environmental Protection guidelines, but against the stricter Canadian Council of Ministers of the Environment limit of 140 mg/kg for lead, 36% of Philadelphia city gardens, 60% of Pittsburgh gardens and 20% of Philadelphia suburban gardens exceeded it — so whether a garden counts as 'safe' or 'over the limit' depends on which standard is applied. In Philadelphia, concentrations generally fell with distance from historical smelter sites, though the correlation was significant only for zinc. Raised-bed soils were lower in lead and arsenic but often higher in zinc, copper, vanadium and nickel, which the authors attribute to ongoing deposition from road traffic and active industry rather than legacy contamination.

Ashley Conway, Christine Nieman · Urban Agriculture & Regional Food Systems · United States

This literature review identifies three key barriers to keeping livestock in US urban and peri-urban agriculture—animal feed resources, water quality and nutrient cycling, and use of heavy-metal-contaminated sites—and argues that agroforestry (silvopasture) practices can help address them. The authors propose two theoretical silvopasture systems, one for urban and one for peri-urban settings, and call for future whole-system research.

Joshua Earl Arnold · Insects · United States (California)

Over two growing seasons, this study sampled brassica crops at urban agriculture sites spanning a gradient of surrounding landscape imperviousness, size, and management to assess parasitic Hymenoptera abundance, richness, and parasitism of the cabbage aphid. On-farm agroecological practices—mulch coverage, floral richness, and crop-plant richness—and larger on-farm noncrop area increased parasitoid abundance, and greater crop-plant richness raised aphid parasitism, supporting the enemies hypothesis in urban agroecosystems.

María Teresa Gómez-Villarino, Teresa Briz · California Agriculture · United States (Berkeley)

This study examined urban gardens in Berkeley, California, and Madrid, Spain, to observe how agroecological principles—efficient, sustainable use of local resources and inputs—are practiced. It reports that gardens using good ecological practices provide a wide range of ecosystem services, including cultural services such as places to socialize, and can serve as model urban agricultural centers contributing to the UN Sustainable Development Goals.

Joshua Newell, Alec Foster, Mariel Borgman, Sara Meerow · Cities · United States (Detroit)

A study in Detroit's Lower Eastside (~15 sq. miles) examined the spatial extent, characteristics, and residents' perceptions of urban gardens using spatial analysis and interviews. Gardens covered less than 1% of vacant land and were often ephemeral. Primary obstacles to scaling up urban agriculture in Detroit include uncertainty over land tenure, environmental pollutants, potential ecosystem disservices, and a lack of government support and capital investment.

Avi Friedman · · Canada (Montreal)

This chapter explores how food production can initiate change at the neighborhood level and how using native flora in landscaping decreases water consumption and benefits local biodiversity. The Benny Farm Project in Montreal, Canada, is presented as an example of a highly productive urban agriculture undertaking.

Nehiby Alcántara Nieves, Rosa María Larroa Torres · Espiral estudios sobre Estado y sociedad · Mexico (Mexico City)

This article investigates the functions of urban gardens in Mexico City two years after the implementation of the Food Sustainability System and the Urban Garden Law. A qualitative study found that public officials tend to prioritize the environmental functions of urban gardens, while for users, the sociocultural functions are the most relevant. The research suggests that urban gardens possess environmental, economic, and sociocultural multifunctionality.

Rachel Bechtold, Catherine W. Shoulders, Jennie Popp, Donald M. Johnson, Lisa S. Wood · Natural sciences education · United States

This study evaluated the process and efficacy of installing a demonstration plot along a multiuse trail in Southeast Kansas to educate the community on rehabilitative plots. The greatest perceived challenges for this case study were the allotment of time and money for initial costs of the demonstration plot and addressing methodology for plant blindness in viewers.

Nehiby Alcántara Nieves, Rosa María Larroa Torres · Espiral estudios sobre Estado y sociedad · Mexico (Mexico City)

This qualitative study investigated the environmental, economic, and sociocultural functions of urban gardens in Mexico City, two years after the implementation of the Law of Urban Gardens (LHU). Data was collected through interviews and document review. It found that public officials tend to prioritize environmental functions, while users consider sociocultural functions most relevant.

Aaron Anderson, Lucas Costner, Lincoln R. Best, Gail Langellotto · Conservation Science and Practice · United States

This study compared the attractiveness of 23 native Pacific Northwest plant species to bees over three field seasons, using timed bee counts and vacuum sampling. It found that Douglas' aster, California poppy, varileaf phacelia, Canada goldenrod, farewell-to-spring, globe gilia, and Oregon sunshine consistently supported high bee abundance and species richness. These findings can inform urban pollinator conservation efforts in gardens and public spaces.

Ainsley C. McStay, S.L. Walser, Eric C. Sirkovich, Nicolas Perdrial, Justin B. Richardson · Journal of Environmental Quality · United States

This study evaluated portable X-ray fluorescence (pXRF) measurements of macronutrients, micronutrients, and toxic elements (As, Pb) in soils and plants from 10 urban community gardens across the eastern United States. It found that pXRF and traditional methods provided agreeable estimates for some elements (Mn, Cu, Zn, Pb) but not for macronutrients (Ca, K, P). While pXRF is an accurate tool for screening Mn, Cu, Zn, and Pb, macronutrients were poorly estimated in fruits, leaves, and roots, and genus-specific and garden-specific factors may be important for plant uptake models.

Joshua Arnold · Processes · United States (California)

A survey of 29 urban farms in the San Francisco Bay Area from 2014 to 2017 examined on-farm spatial composition, management practices, and estimated productivity. Findings showed a large proportion of farm area dedicated to infrastructure and underutilized potential production space. All surveyed farms adopted diverse agroecological practices, and measured farms were productive with estimated seasonal yields of 7.14 kg/square meter, comparable to actual yields at two farms.

Cara A. Rockwell, Alex Crow, Érika R. Guimarães, Eduardo Recinos, Deborah La Belle · Urban Planning · United States

Tree species richness, stem density and canopy cover in food forest gardens at 10 public schools in Miami-Dade County, Florida, were investigated and compared with results from neighboring properties around each school. Food forest canopy cover was comparable to neighborhood urban tree cover, while arborescent species richness — including a greater share of edible taxa — and stem density were both higher in food forests than in adjacent neighborhood plots.

Gustavo Henrique [UNESP] Pereira da Silva, Margarete Cristiane de [UNESP] Costa Trindade Amorim · LA Referencia (Red Federada de Repositorios Institucionales de Publicaciones Científicas) · Brazil

A study in Florianopolis, Santa Catarina, Brazil, analyzed the effect of urban agricultural areas on atmospheric heat island intensity. Data were collected in February 2019 at 12 fixed points spanning three urban agricultural areas, eight intra-urban areas, and one area without construction materials. During daytime (9 a.m., 3 p.m.), points located to the south of the island of Santa Catarina—including urban agriculture sites—recorded the highest air temperatures, while at night temperatures decreased overall, with the studied agricultural areas becoming 'islands of freshness' relative to surrounding areas on many days.

Cristiane Veeck, Renata Menasche, Carolina Borges · AntHropológicas Visual · Brazil

A photo essay documents the relationship between hibiscus (Hibiscus sabdariffa) and humans at the Horta Comunitaria da Lomba do Pinheiro, a collective agroecological urban agriculture project in the eastern zone of Porto Alegre, Rio Grande do Sul, Brazil, begun by community initiative in 2011. Following a growing cycle that begins with sowing around August and ends with harvest between February and May, the plants trace back roughly eight years to seeds obtained from an agroecological farmer nearby; the harvest season ends with jam-making workshops, and the informal sale of dried hibiscus provides funds for maintaining the garden.

Judy Orton · Digital Archive @ GSU · United States

Two studies examined ecology-centered experiences — experiences with living things — among children and adolescents in the United States. Study 1 was a yearlong ethnographic study at an urban community garden in a large city in the southeastern United States, finding through participant observation and informal interviews with staff and participants that children had opportunities to learn about ecology through such experiences. Study 2 found that ecological thought — a pattern of thinking that privileges relationships between living things — did not predict environmental attitudes and behaviors, and that while ecology-centered experiences alone did predict environmental attitudes and behaviors, this predictive relationship disappeared once environmental responsibility support was taken into account.

Daria Ponstingel · Socio-Ecological Practice Research · United States (Austin)

A 2022 study of community gardens in Austin, Texas, USA, examining the approaches used to govern them and the socio-ecological outcomes associated with each model. Using Ostrom's socio-ecological systems framework, the author combined key-informant interviews with garden managers (yielding both qualitative and quantitative data) with remote-sensing estimates of net primary productivity — a proxy for carbon sequestration — derived from ECOSTRESS imagery on the International Space Station and Planet Inc. data. Social outcomes were measured as gardeners' satisfaction and perceived success; ecological outcomes as green-space ecosystem services. The highest social and ecological performance was found in gardens with 'bottom-up' governance structures, where community members hold decision-making and management authority. The author argues the two kinds of outcome are codependent and that the governance approach determines the form that codependence takes. The study covers gardens in a single city, so generalisation elsewhere remains to be tested.

Guzzon F., Arandia Rios L.W., Caviedes Cepeda G.M., Céspedes Polo M., Chavez Cabrera A., Muriel Figueroa J., Medina Hoyos A.E., Jara Calvo T.W., Molnar T.L., Narro León L.A. · Agronomy 11(1):172 · Latin America

Reviews the fundamental role of Latin American maize landraces for food security, livelihoods and culture, the threat of genetic erosion, and the current state of their conservation and use.

Moisés Savian, Pedro Boff, Mari Inês Caríssimi Boff · Research Society and Development · Brazil

This study analyzed the contribution of urban agriculture to sustainable development in Brazilian cities and communities by reviewing 40 scientific articles published between 2009 and 2019. The findings indicate that urban agriculture is practiced across all regions of Brazil, exhibits diverse multifunctional characteristics, plays a significant role in maintaining agrobiodiversity, and supports food and nutritional security. It also contributes to economic, social, and ecological aspects of cities, potentially benefiting urban spaces, promoting health, and aiding educational processes.

Alessandra Pavesi · · Brazil

This paper presents a conceptual and methodological approach to analyze and foster Cerrado (Brazilian savannah) cultivation in urban settings, focusing on collaborative learning processes. Based on cultural historical activity theory, it reframes urban farming for Cerrado regeneration from a systemic, developmental, and participative perspective. The approach aims to help practitioners identify and manage internal and external tensions within the activity system by rethinking its object and designing new actions and artifacts.

Rachel A. Brant, Gerardo R. Camilo · Insects · United States (Chicago)

Body size variation in female Halictus ligatus sweat bees collected from Chicago, Detroit, and Saint Louis between May and October 2016 was compared. Head width and intertegular distance were measured in bees collected from community gardens and urban farms. ANCOVA analysis indicated significantly different body size ranges across the three cities, and temperature also had a significant influence on body size.

Noelle Morrow, Megan Kadzirange, V. Smith, Nirusha Thayaal, Ngaire Barraclough · Open Collections · Canada (Vancouver)

This infographic is based on the article "Beyond feeding the city: The multifunctionality of urban farming in Vancouver, BC" by Valley, W., & Wittman, H. (2019). It is an undergraduate student work resulting from a collaboration between the Making Research Accessible initiative (MRAi), researchers, and ASTU 100 students at UBC. The lead author of the original article reviewed the student work, and their revisions were incorporated.

Alexandra Cavalcante Salomão Silva, Sávio Tadeu Guimarães · Programa de Iniciação Científica - PIC/UniCEUB - Relatórios de Pesquisa · Brazil (Brasília)

This study investigated the activities of the urban agriculture project "Coletivo Re-Ação Agroecológica" in idle public spaces in Brasília, using a case study and action research. The research aimed to identify factors that encourage and hinder urban agriculture projects, emphasizing it as a component of sustainable urbanism. Results indicate that urban agriculture should be encouraged by the state through practical and less bureaucratic public policies, and interpretive trails in urban farms support the dissemination of educational information, bringing people closer to nature.

Vidya Anderson, William A. Gough · International Journal of Biometeorology · Canada (Toronto)

A controlled field study in Toronto, Ontario, Canada, evaluated the impact of multiple types of green infrastructure on near-surface air temperature regulation. Over two summers, a field campaign measured the impact of green roofs, green walls, urban vegetation and forestry systems, and urban agriculture systems on near-surface air temperature. This study demonstrated that multiple types of green infrastructure applications are beneficial in regulating near-surface air temperature and are not limited to specific treatments.

Rachel Wilson · Science and Children · United States

As part of a school garden project, second graders in the United States participated in integrated lessons exploring ladybug life cycles, culminating in the release of beneficial insects in our school garden. The unit aimed to connect life cycle concepts to a new organism, using a 5E format and integrating language arts activities. This approach met both science content objectives and English Language Arts standards.