Research & reports

Josselin Rouhier · · Europe

Shared gardens are a powerful support for social connection, enabling collective activities and participatory consultations that foster exchanges and interactions among various stakeholders. They serve as a meeting point for administrations, developers, associations, and residents. Shared gardens are presented as an example of sustainable development, promoting intergenerational communication and socio-professional diversity within urban natural spaces.

Rosanne Wielemaker, Jan Weijma, G. Zeeman · Resources Conservation and Recycling · Netherlands (Rotterdam)

This paper assesses the match between supply from New Sanitation (NS) systems and demand from Urban Agriculture (UA) for nitrogen, phosphorus, and organic matter in Rotterdam. Using the Urban Harvest Approach, the research found that UA's demand for nutrients and organic matter can be minimized by 65–85%, achieving 100% self-sufficiency for phosphorus and partial self-sufficiency for nitrogen and organic matter. The integration of NS and UA maximizes urban self-sufficiency.

Andrew Hursthouse, T. E. Leitão, Annette Voigt, Avigail Heller, Béatrice Bechet, Paulo Brito da Luz · HAL (Le Centre pour la Communication Scientifique Directe) · Europe

This chapter overviews factors influencing the chemical, physical, and biological status of soils, water, and the biosphere in urban allotment gardens. It highlights that urban garden soils, water, and biosphere are affected by pollution due to their location in city centers or suburbs, with traffic infrastructure and industrial zones widely identified as impacting soil and water quality. Concerns over long-term risks from pollutant transfer (mainly metals) from soil to plants in these uncontrolled environments have been widely publicized.

Alexandra Doernberg, Ingo Zasada, Katarzyna Bruszewska, Björn Skoczowski, Annette Piorr · Sustainability · Germany

A 2016 study applies a food systems approach to examine the potential and limits of regional organic food supply in the Berlin Metropolitan Region (BMR), Germany. Using an analytical framework built from the literature and qualitative interviews plus a stakeholder workshop on two alternative food network types — organic community supported agriculture (CSA) and organic retail trade — it finds that demand for regional organic food exceeds regional supply, while identifying obstacles including limited access to land, rising rental prices, insufficient processing capacity, and an unsupportive political environment for organic farming.

Rosanne Wielemaker, Jan Weijma, G. Zeeman · Resources Conservation and Recycling · Netherlands

A study on Rotterdam, the Netherlands, assessed how source-separation-based New Sanitation (NS) systems could match the supply of nitrogen, phosphorus, and organic matter with demand from Urban Agriculture (UA), premised on the view that sustaining cities long-term requires a circular metabolism where the output ('waste') of one urban process becomes input for another. Applying the Urban Harvest Approach, originally developed for the urban water cycle, to nitrogen, phosphorus, and organic matter across two UA typologies (ground-based and rooftop) and four NS concepts treating domestic urine, feces, and organic kitchen waste, the study found that UA's demand for nutrients and organic matter could be reduced by 65-85%, with full (100%) self-sufficiency achievable for phosphorus, while nitrogen and organic matter would reach only partial self-sufficiency.

Baptiste Grard, N. Bel, Marchal, Nicolas, Frédéric Madre, Jean‐François Castell, Philippe Cambier, Sabine Houot, Nastaran Manouchehri, Stéphane Besançon, Jean‐Charles Michel, Claire Chenu, Nathalie Frascaria‐Lacoste, Christine Aubry · Kobra (Universitätsbibliothek Kassel) · France (Paris)

A 2012 pilot experiment in Paris, France, tested simple rooftop gardening systems using local urban organic waste as crop substrates. Measurements of production levels and heavy metal content in crops and substrates showed high crop production with limited inputs, low heavy metal pollutants in edible parts, and positive yield influence from layered substrates and earthworm inoculation. These results suggest rooftop gardening is feasible and has potential for urban resiliency, though further assessment of roof types, pollution levels, and sustainability is needed.

Miren Rekondo Iparraguirre · TDX (Tesis Doctorals en Xarxa) · Europe

This doctoral thesis explores the development of eco-citizenship competence in school gardens, specifically through collaborative technological design activities. Elementary school students designed and assembled an irrigation system for their school garden over ten activities. Analysis showed students integrated elements from various design proposals without exclusive opposition, and that design conflicts led to a more dynamic and complex garden model. The study also found differences in argumentative discourse structure and dynamics between scientific argumentation and technological design activities.

Greg Keeffe · Research Portal (Queen's University Belfast) · United Kingdom

This chapter focuses on developing sustainable growing infrastructure at two scales: a large-scale city-wide fuel-productive landscape using algae arrays in Liverpool and a hyper-localized neighborhood food production system in Salford, UK, utilizing a closed-cycle aquaponic system. The author proposes a three-part model for urban agriculture implementation—hardware, software, and interface—concluding that urban agriculture should be viewed as a process rather than a static design, with benefits extending beyond physical outputs like energy and food.

Emmanuelle Vaudour, Christine Aubry, Liliane Bel, Laëtitia Bréchet, Philippe Cambier, Yves Coquet, Karim Dhaouadi, Veronique V. Etievant, Benoît Gabrielle, Jean-Marc J.-M. Gilliot, Jean Christophe Gueudet, Dalila Hadjar, Jonas Hamiache, Sabine Houot, Christophe Labat, Patricia Laville, Raia Silvia Massad, Joël Michelin, Paul Emile Noirot Cosson, Jean-Noël Rampon · HAL (Le Centre pour la Communication Scientifique Directe) · France

The PROSTOCK project aimed to spatially assess the potential of recycling organic waste (exogenous organic matter, EOM) to improve soil organic carbon stocks (SCS) in peri-urban agricultural areas. It also evaluated the impacts of EOM use on greenhouse gas emissions and nitrate leaching. The Versailles Plain and Alluets Plateau (221 km²) were chosen as the study region, with field and lab measurements collected from over 250 point locations. The project advanced the use of imaging data for estimating topsoil organic carbon content (SOC) from soil reflectance spectra, but found that medium spatial resolution multispectral satellite images do not discriminate changes in SOC resulting from EOM applications.

Jill L. Edmondson, Zoe G. Davies, Kevin J. Gaston, Jonathan R. Leake · Journal of Applied Ecology · United Kingdom

This study compared soil quality indicators (soil organic carbon storage, total nitrogen, C:N ratio, and bulk density) in urban allotments, surrounding agricultural land, and other urban greenspaces in a typical UK city. Allotment soils showed 32% higher soil organic carbon concentrations and 36% higher C:N ratios than pastures and arable fields, and 25% higher total nitrogen and 10% lower bulk density than arable soils. The study reported no significant difference in soil organic carbon concentration between allotments and urban non-domestic greenspaces, but it was higher in domestic gardens beneath woody vegetation.

Géraldine Farges · Sociologia Ruralis · France

This one-year ethnographic study analyzed the integration of pro-environmental practices among amateur gardeners in a French urban allotment. Through observations and repeat interviews, it found that while gardeners adopted new techniques, the meanings of their practices and their environmental relationships differed. The diffusion of pro-environmental practices was not systematically linked to shared concerns, and practices were interpreted differently by policymakers and individuals.

Anna Gaviglio, Alberto Pirani, Mattia Bertocchi · Advanced engineering forum · Italy (Milan)

This study assessed the environmental, social, and economic sustainability of farms within the South Milan Agricultural Park (PASM), based on interactions between the Milan metropolitan area and surrounding agricultural activities. The survey was conducted using an indicator-based tool to compare farms, with data collected from various sources. Results indicated that PASM's efforts provided valid economic tools for large multifunctional farms, deeply tied to the local context through services like direct sales, short chains, and agritourism, contributing to improved environmental conditions and landscape. However, large and small specialized farms lacking these income sources did not receive equal contribution.

Migge L., Haney D. H. · Dumbarton Oaks Research Library and Collection (Ex Horto series); Harvard University Press · Germany

An annotated English translation (edited and introduced by David H. Haney) of Migge's foundational 1913 treatise, presenting the primary source for his social and productive garden theory, from urban parks to housing settlements with allotment gardens.

Jaquand C. · In Situ. Revue des patrimoines, no. 21 · Germany

Examines Migge's landscape designs for urban extensions in Berlin, Frankfurt and Dessau and his organic city-garden relationship based on recycling water and urban waste, including the evolving self-sufficient settlement system of his 1932 book.

Jill L. Edmondson, Zoe G. Davies, Sarah A. McCormack, Kevin J. Gaston, Jonathan R. Leake · The Science of The Total Environment · Europe

A study of Leicester, a mid-sized city in the United Kingdom (73 km², 56% greenspace), analyzing how land-cover type (herbaceous, shrub or tree cover) affects soil organic carbon (SOC) stocks. Topsoil SOC was measured in domestic gardens and non-domestic greenspaces and compared with surrounding extra-urban agricultural land, then mapped citywide. Average SOC storage across the city's greenspace was 9.9 kg/m² to 21 cm depth; SOC under trees and shrubs in domestic gardens exceeded all other land-cover types, with median total storage of 13.5 kg/m² to 21 cm depth — more than 3 kg/m² higher than any other land-cover class in domestic or non-domestic greenspace, and 5 kg/m² higher than arable land. Land-cover did not significantly affect SOC in non-domestic greenspace overall, though values under trees were higher than under pasture and arable land, while shrub and herbaceous cover were higher only than arable land. The study concludes that greenspace management affects SOC stocks, that trees only marginally increase stocks in non-domestic greenspaces but may enhance them in domestic gardens, and that greenspace topsoils hold substantial SOC stores requiring protection from further expansion of artificial surfaces such as patios and driveways.

Manuel Ângelo Rodrigues, Diana Peixinho, Sílvia Nobre, Paula Sara Teixeira de Oliveira, Margarida Arrobas · · Europe

Noting that, in developing countries and in developed countries during periods of economic depression, creating land for urban agriculture has served as a politically significant instrument to strengthen food security and ease poverty and unemployment, and that more recent urban agriculture projects in developed-country cities aim to enhance social activity and quality of life, this paper reports on the "social gardens" project run by the Polytechnic Institute of Bragança (IPB), Portugal, since 2011. It reports on some practices with high agroecological significance adopted by the gardeners, namely organic fertilization, composting, mulching, intercropping, and shelter systems.

Vesna Popović, Jelena Živanović Miljković · Institute of Agricultural Economics eBooks · Europe

A study analyzing trends in community gardening in Europe, with particular focus on Belgrade, Serbia, in relation to permaculture design principles. It notes that while intensive urban agriculture carries ecological risks related to soil, water, air, climate, biodiversity, and landscape, citizens seeking healthy food and closer contact with nature are turning toward extensive, often organic, forms of urban agriculture such as community gardening based on permaculture design, and it discusses the role of such gardening in smart-city development and its establishment potential in Belgrade.

Javier Varona Espallargas · RECAM Metropolitan Knowledge Repository · Spain (Barcelona)

This study analyzes community self-composting at the L'Hortet del Forat urban community garden in Barcelona, Spain. It aims to assess the potential for waste prevention and management, and to identify the social characteristics of users engaging in this practice.

Richard Oram · Stirling Online Research Repository (University of Stirling) · United Kingdom

This paper reviews geoarchaeological evidence and analyzes documentary records from 17 Scottish burghs to explore waste management and peri-urban agriculture in early modern Scotland. The study illustrates the central role of urban waste as manure in burgess agriculture. Burgh regulations revealed changing cultural attitudes towards waste in the 17th and 18th centuries, but urban waste remained in demand as fertilizer in the hinterland of many Scottish towns until the late 19th century.

Alma Clavin · Local Environment · Europe

This paper reports on the multiple impacts that community garden design may have on the subjective well-being of site users, using the capability approach as a normative framework. Qualitative research conducted in five community garden sites in the UK and Ireland in early 2011 yielded new explanations for both sustainable design and well-being. Two key design aspects, agency and dynamic balance, were found to enhance both the sustainability of the community garden sites and the well-being of site users.

Steffen Lehmann · Journal of Green Building · Europe

This paper discusses resource recovery and materials flow in cities, noting that urban farming has emerged as a valid urban design strategy in Europe, contributing to local food production, organic waste composting, and biodiversity. It reports on best practices for implementing zero waste, including adaptive re-use and design for disassembly, and identifies that the construction and demolition sector is a major waste producer. A key finding is that achieving 'zero-waste' requires strong industry leadership, new policies, effective education, and refocused research agendas.

Haney D. H. · Routledge · Germany

The first book to fully document Migge's life and work, presenting him as a central figure across garden reform, urban planning, the Siedlungen housing movement, and organic architecture and planning, with extensive archival illustrations.

European Commission · European Commission — Directorate-General for Environment · Europe

This European Commission page on the Waste Framework Directive states the directive entered into force on 12 December 2008. It notes the EU generates around 2.5 billion tonnes of waste per year (roughly 5 tonnes per person annually). An amended version, effective 16 October 2025, includes food-waste reduction targets.

Haney D. H. · Landscape Journal, 26(2), 201-218 · Germany

Analyzes Migge's 1919 'Green Manifesto', one of the most overtly political tracts by a landscape architect, proposing that intensive vegetable gardens for everyone could solve Germany's social and economic problems through a technologically modern synthesis of garden and dwelling.

Arjan van Timmeren, Daniel Sidler, Marleen Kaptein · Journal of Green Building · Europe

This paper is a case study of the integration of a combined wastewater/energy system into a semi-public building, the EVA Centre, within EVA Lanxmeer, a "deep green" district in Culemborg, the Netherlands, consisting of 250 houses, offices, and a City farm. The district lies in an ecologically sensitive drinking-water extraction and retention area, and the approach centres on closing nutrient, water, and carbon cycles and integrating energy generation with waste management using the concept of exergy. The core system is based on anaerobic digestion (treating black wastewater and garden/park waste) combined with Combined Heat and Power generation, alongside a four-storey double-skin-façade closed greenhouse with vertical "hanging gardens" that incorporates wastewater treatment based on the Living Machine concept for educational purposes, recovering surplus CO2 from the biogas plant and storing heat/cold in an underlying aquifer. This "Sustainable Implant" concept is described as connecting the residential district and the EVA Centre, and its inhabitants and visitors.