Global Health as Vector for Agroecology in Collective Gardens in Toulouse Region (France)

Abstract

Agroecological transitions in collective urban gardens in Toulouse region were studied through the prism of global health (2011–2022). The specific meaning of “global health” in the context of urban gardens concerns the health of gardeners (well-being and physical health), plants, soil, and animals, as well as the interactions between humans and non-humans, which are crucial for gardeners. A sociotechnical research project was developed on four different collective gardening sites, consisting of the following: 1. surveys issued to 100 garden stakeholders to highlight issues and practices, participation in meetings with the social centers in charge of events, and focus groups; 2. participative agronomic and environmental measurements and field observations, including soil quality analyses; and 3. analysis of the available documentary corpus. In order to produce the results, these three research methods (surveys, agronomy, document analysis) were combined through a transdisciplinary approach, in that both the field experimentation outcomes and retrieved scientific publications and technical documents informed the discussions with gardeners. Consideration of the four different sites enabled the exploration of various contextual factors—such as soil or air quality—affecting the production of vegetables. A rise in the concerns of gardeners about the impacts of their activities on global health was observed, including aspects such as creating and enjoying landscapes, taking care of the soil and biodiversity, developing social connections through the transmission of practices, and regular outside physical activity and healthier eating. The increased consideration for global health issues by all stakeholders promotes the implementation of agroecological practices in gardens to improve biodiversity and adherence to circular economy principles. Four concepts emerged from the interviews: health, production of vegetables, living soil, and social interactions. Notably, nuances between the studied sites were observed, according to their history, environment, and organization. These collective gardens can thus be considered as accessible laboratories for social and agroecological experimentation, being areas that can strongly contribute to urban ecosystem services.

1. Introduction

A strong interest in urban collective gardening activities has been observed on a global scale, with increasing recognition of the benefits of nature in the city, such as those relating to biodiversity [1], as well as economic crises and global health [2,3]. In response to land pressure, many cities in France have developed collective gardens. However, in urban areas, space is scarce and often polluted; as such, the question of soil quality is a concern for the managers of collective gardens [4,5].

The sustainable development of urban collective gardens requires a rigorous, multi-criteria, and multi-stakeholder sociotechnical methodology, including historical study, surveys to inform gardening practices, quality characterization of soils and plants, and assessment of potential sanitary risks [6]. Gardeners’ associations are particularly considerate of soil health, as it influences fertility, crop quality, water and carbon storage, and biodiversity [7,8,9]. There is increasing concern regarding the practices and ethics of caring for the living soil, politics of soil knowledge, and soil–human relationships [10,11]. Moreover, in France, regulatory developments have transformed gardening practices: since 2017, the Labbé law (Law n° 2014-110 of 6 February 2014) has prohibited individuals from using phytosanitary products for the maintenance of green areas which are accessible to the public. Soil protection has also been highlighted in the public space, with the Climate and Resilience Law 2021-1104 setting a target of “zero net artificialization” by 2050. In order to more precisely understand the global health concept,

Table 1. Comparison between soil and human health.

Soil Characteristics	Human Characteristics
Living soil with microorganisms is more resilient and provides ecosystem services.	A healthy human can cope more easily with stresses and can provide more services to society.
Routine, simple, and inexpensive tests characterize soil (pH, texture…). Comparison of the measured results with reference values from empirical studies, contextualized databases (region, climate, soil) can then be performed for the purpose of making a diagnosis.	Simple and inexpensive measures characterize a human (weight, height, sight test…). Comparison of the measured results with reference values from empirical studies, contextualized databases (for a given country, gender, age, etc.) can then be performed for the purpose of making a diagnosis.
Historical study of the site.	Family history.
Land use.	Professional practices.
IEM: check the adequacy of soil characteristics and its utilization with a quality grid.	Status (pregnant woman, young child, etc.) in relation to practices, exposure to toxic pollutants.
Remediation, action plan	Treatment, surgery, etc.

illustrates the parallels between soil and human health, as two complex and dynamic ecosystems.

This study first aims to describe the characteristics (social, agronomic, environmental, and health) of urban collective gardens managed by the city of Toulouse, which is characterized by a strong agricultural tradition and demographic growth, and has experienced a significant dynamic of creation and support for urban collective gardens in recent years. Then, issues of global health concerning the health of gardeners (well-being and physical health), plants, soils, and animals are studied, along with an evaluation of the ecological performance of these public areas. The research question explored in this study is as follows: “Is global health a vector for agroecology in urban collective gardens in Toulouse region (France)?” In this context, health is understood as a global concern for humans, living organisms, and the environment.

2. Materials and Methods

2.1. Global Scientific Design

Interdisciplinary research was carried out based on: 1. surveys of garden users and managers (gardeners, site coordinators, engineers, and elected officials of the city of Toulouse), respecting the RGPD French regulation for personal data protection, and field observations of participants to shed light on the uses and roles of gardens; 2. measurements (soil quality and plant production) and field observations regarding biodiversity, agricultural practices, and human interactions. Between 2011 and 2022, in collaboration with the Toulouse Department of Solidarity and Social Cohesion, agronomic, environmental, health, and social data were acquired. The research work was first carried out as part of the “Jassur” national project on urban collective gardens, supported by the ANR (2014-18) and piloted in Toulouse by PR C. Dumat (Certop and Dynafor). Then, educational and research projects were supported by the CNRS or Ademe and carried out in collaboration with engineering, doctoral (W. Jules), or master’s students from Toulouse University (agronomy, ecology, and environmental sociology). The four collective garden sites used for the analyses are detailed below.

In order to produce the results, the three research methods (surveys, agronomy, document analysis) were combined through a transdisciplinary approach, with both field experimentation and scientific publications and technical documents informing discussions with gardeners. Moreover, for comparison of the sites, the four words most used by gardeners to describe their goals were noted during the interviews and classified for each site.

2.2. Survey

The relationships between gardening activity and health (physical activity, well-being, biodiversity of plants and insects) were studied through field observations, measurements, and semi-directed interviews with 100 gardeners, site coordinators, engineers, and elected officials of Toulouse. Two phases were performed: 1. Discovery, and 2. interviews. Documentation produced by the gardening associations was also used, including articles, charters, brochures, and websites. The analysis phase was then carried out according to the following axes:

1. Interviews with the actors, open observations, collection of documents, expression of feelings, and cross-checking of data.

2. Analysis of the gardening activity: time spent, family activity or not, sharing of knowledge, cultivation practices, and knowledge of the risks and health benefits associated with gardening.

A total of 100 gardeners were surveyed regarding their practices, environmental health concerns, projects, and the meaning that they give to their gardening activities. Individual semi-structured interviews and focus groups [12] were performed to obtain complementary data and observe the production of meaning in action [13]. The argumentative logic was then analyzed, and “verbatims” concerning the same themes were grouped together to shed light on the main observed trends.

2.3. Soil Study

For all the sites, the quality of the soil was studied (with respect to current agronomy and metal pollution: Pb, Cd, Cu) and discussions with gardeners on the relationship between the environment and health were conducted. Questions discussed with gardeners related to their perceptions, knowledge, and definitions of soil fertility and soil health; the factors influencing their choice of crops and their cultivation patterns; informal exchange networks, interactions, collective learning processes, and communities of practice; and the evolution of knowledge and know-how with regard to expertise, both built up before arrival in a collective garden and after. We further assessed quantitative data on harvests [9] obtained from questionnaires, interviews with gardeners, and observations of the plots.

2.4. Characteristics of the Studied Gardening Sites

Four contrasting collective gardens in the Toulouse region were studied in terms of their contextual effects (i.e., in agronomic, environmental, health, and/or social aspects) on the evolution of cultural practices in relation to health–environment issue. They were the shared and family gardens of Monlong, La Périole in Balma (family), Tournefeuille (collective), and Blagnac (collective and educational). The codes used for the collected information are as follows: the name of the site, then G for gardener, A for event, a number to indicate the various contributors, and gender (M for man or W for woman). To respect the anonymity of the gardeners, their first names have been changed. Details of each garden site are provided below, including their environmental and organizational contexts, which are likely to influence the practices and perceptions of gardeners.

Collective and family gardens of Monlong: Inaugurated in 2010, these gardens are the result of a co-constructed project between citizens and the Social Center (CS). The shared gardens of Monlong, which are watered by Gallo-Roman springs, are located in a 4-hectare wooded park that is open to the public. A total of 69 individual plots and 2 collective plots are cultivated. Biodiversity is important in this site, with 176 plant species having been identified. The Bellefontaine Social Center manages the two gardens, which organizes events concerning biodiversity and food, the distribution of plots, and the management of conflicts. The Monlong site is located near a waste incinerator which has the French status of a regulated plant for environment protection (ICPE in France). Gardens are located in the main axis of the winds and, therefore, are exposed to discharges from the incinerator. An Owen gauge installed in the nearby Eisenhower station (n°78) makes it possible to assess the possible atmosphere pollutant load induced by the waste incinerator (Figure 1). Located in a working-class area, food is a crucial point, and education for sustainable food has been proposed by agents from the city. Here, the gardeners mainly want produce vegetables and share good times around meals. Several meetings and events reinforce this idea (see

Table 2. Events attended by the gardeners at the Monlong site.

Event	Themes and Description
Jams	Optimization of the end of season harvest. Objective: sale for the Telethon. Ex. Green tomatoes with ginger, cinnamon, lemon.
Meals	Back-to-school meal for gardeners, prepared outdoors with vegetables from the garden accompanied by homemade preparations.
Workshop	“Caring for plants by plants.” 1. Identification of protective plants on the spontaneous flora plot of the DIRE association. 2. Disease/pest = which plant? 3. Collection of useful plants for preparations: infusions, decoctions, and liquid manure.
Workshop	Training “know your plot.” 1. Soil structure and its differences. 2. How to recognize them?
Museum	In the botanical garden, promoting nature in the city: “Valuing the work of gardeners.” 1. Presentation of vegetables (e.g., squash); 2. tasting of pumpkin soup, jams…
Workshop	“Knowing your plot” and cultivation methods. 1. Soil structure, balance, needs… 2. Cultivation practice, precautions… 3. Indicator plants. 4. Natural sewage… 5. Crop plant needs… 6. Approach to green manure.
Workshop	Green fertilizer workshop and restitution of soil metal analyses.
Workshop	Market gardening mound training workshop. 1. Making a permaculture mound: the different sofas. 2. Optimize garden/kitchen waste.
Meals	Departure of a facilitator from the Régie de Quartier. Thank-you meal consisting of house specialties.
Telethon	Raise funds for charity through the sale of garden produce.

. Events proposed to the gardeners in Monlong site). These individuals take advantage of the garden environment to meet people and maintain gentle physical activity. However, air quality is a concern due to the proximity of the waste incinerator.

Périole family gardens in Balma: These gardens are located next to the Toulouse ring road and are visible from the metro which stops at the Balma Gramont terminus. The Hers Mort River is the main source used to irrigate the gardens. The quality of the river water is regularly monitored: “in 2020, out of 150 molecules of phytosanitary products sought, 21 were detected on a regular basis, most often at low doses. Hydrocarbons from runoff from the highway are sometimes observed” (Balma-A1). Originally, these were allotments made available by landowners in Toulouse, who founded the association in 1905. This historical context of “allotments” anchors them with a primary objective of food production; that is, 2/3 of the plot must be devoted to vegetable crops. However, environmental issues have developed significantly since 2015, when a charter prohibiting pesticides in gardens was validated by the Board of Directors.

“The use of chemicals was still discouraged in the gardens”.

(Balma-A1)

On the 4 hectares of the Périole gardens there are 200 plots of various sizes (100 to 250 m²), some with sheds. The average age of gardeners is 60 (being mainly retirees). This site is characterized by a thorough organization, with managers for different sectors and agroecological formations proposed to gardeners interested in food production and soil quality.

Collective gardens of Tournefeuille: Since 2003, the association Tour’sol, in addition to gardening, has coordinated courses and events for both its members and the general public (https://www.jardiniersdetournefeuille.org, 6 January 2025). The allotment gardens offered to citizens are laid out on 2 hectares of municipal land between the green corridor of Touch and the “Phare” car park, with a total of 72 plots (from 70 to 250 m²) for families, educational plots intended for schools, leisure centers, specialized structures, and integration plots. To mix citizens, the allocation of plots is carried out in order of arrival on the waiting list. At present, the population of gardeners comprises 54% men, 28% women, and 18% couples, with most being retired persons. The philosophy of the association “is that gardening makes it possible to cultivate vegetables, body, mind, social ties at the same time,” thanks to education for “natural” gardening to support biodiversity. The president of the association (D. Dupouy) has affirmed its desire to “make these gardens pleasant, so that visitors take pleasure in observing the challenges of biodiversity.” In 2018, a second family garden site was created by the association: “Jardin des Ramée-Culteurs.” Due to its history and the interest of the Tournefeuille mayor in ecology, the two sites in Tournefeuille are particularly active regarding the development of agroecological practices, citizen network formation, and dispositive concerns such as refuges for insects or mature plants.

Blagnac urban gardens in the Quinze Sols area: Since 2011, these gardens have been developed on a 3-hectare non-buildable flood zone, offering 75 plots to gardeners, with a shed, a rainwater collector, and a composter. A gardening charter promotes agroecological practices, biodiversity, and human health.

“In a political context wishing to develop local agriculture, the City of Blagnac has set up family gardens in the Quinze Sols” (Blagnac-A1). Two collective gardening plots coordinated by the city are open to the residents of Blagnac, including a group of seniors. “The association of small Caouecs” develops activities for the environmental education of kindergarten-aged children. However, the gardeners shared concerns regarding soil fertility as, when the gardens were created, topsoil was partly removed to form a dike: “Soil is not rich enough in organic matter, because of the stripping during the installation” (Blagnac-J1).

An agri-environmental participative research project with gardeners permits the exploration of both soil quality and the transmission dynamics of knowledge and practices. Figure 2 shows a map view of the gardens. While topsoil excavation has effectively induced low soil fertility, soil amendments are being conducted with the aim of gradually improving this situation.

3. Results

3.1. Collective Urban Garden as Public Dispositive to Promote Global Health

A rise in gardeners’ concerns about the impacts of gardening on global health (human, environmental, biodiversity) was observed for all four sites, including the aspects of creating and enjoying landscapes, taking care of the soil (and, more broadly, of nature), developing social connections through the transmission of practices, and regular physical activity and healthier eating. Increased consideration of health issues by all stakeholders was observed, including systematic analyses of pollutants to avoid human exposure, as well as the implementation of agroecological practices for the promotion of biodiversity. When questioned about their priority goals, four concepts systematically emerged from the interviews with gardeners: Health, production of vegetables, soil, and social interactions. However, nuances with respect to environmental care and global health arose between the four sites, according to their characteristics (e.g., history and type of organization).

Table 3. Results concerning the main goals of gardeners: (a) classification for each site and (b) the various complementary ideas proposed by the gardeners for each of the four main goals.

(a)
	Health	Production	Social Interactions	Soil
Tournefeuille	3	2	4	1
Balma	3	1	4	2
Monlong	2	1	4	3
Blagnac	4	2	1	3
(b)
	Health	Production	Social Link	Soil
Complementary words	Mental health, Physical health, Risks, Pollution, Biodiversity, Pleasure, Soil, Environment.	Food, Diversity, Original varieties of vegetables, Quality, Pollution, Savings, Offerings.	Education, Transmission, Links, Pleasure, Collective organization, Sustainable, Negotiation.	Environment Biodiversity, Insects, Earthworms, Organic materials, Care, Transmission.

presents the results concerning the main goals of gardeners, including the classification for each site and the various complementary ideas of gardeners regarding each of the four main goals. We observed that gardeners made clear connections between agroecological practices, soil life, biodiversity, and their health. Exposure to pesticides, interactions with nature, and the potential impacts of anthropogenic activities were notable in the cases of the two sites where the surrounding environment raised concerns (i.e., roads, nearby industry).

The questioned gardeners had diverse profiles: young workers, men and women, often with dependent children, and a majority of retired people spending more than 5 h per week in the garden. A great diversity of life paths and motivations was observed, and this strong mix was also evident in the gardening techniques and cultures. The desire to increase a certain food autonomy and a healthier diet was widely observed; it is the means of achieving this goal that differed. The majority of gardeners on individual plots (60% in 2021 compared to 80% in 2011) affirmed that plant production is crucial, which led to the implementation of more traditional practices that were deemed to be proven in the field. In Balma, as the gardens were initially created as “worker’s gardens” to offer a food supplement to the workers, food production is crucial; even if, at present, individuals in other socio-professional categories have access to the gardens. The more recent gardens in Tournefeuille and Blagnac strongly address ecological and health issues. The gardeners are particularly sensitive to the environment and soil life, and include reflections on their environmental impacts in their practices, as in agroecological or permaculture principles. Moreover, 95 gardeners spoke of their interest in joining collective gardens for social purposes (95%).

At the Monlong site, in order to obtain a representative panel, the availability of gardeners led us to extend the period of the survey: a third of the members (around 30) were surveyed (between 2015 and 2018, during and outside the office hours) regarding environment and health issues. The questionnaire was based on their perceptions, in order to identify the feelings of the gardeners in terms of what is achieved, as well as what is expected. The collective plots with heterogeneous plantations, where everyone recognizes themselves and shares their knowledge, welcome schools and patients from the day hospital to help them find physical and social activities.

“It’s the openness and reception of all public since gardeners told us, it’s good to meet old and young people, children and also people with disabilities. Differences are erased on the gardening activity”.

(Monlong-A)

Conflicts do not disturb the functioning of the collective, and sometimes seem necessary: being able to express differences in a non-violent way is appreciated by gardeners, and the social center provides mediating measures. Each day in the shared garden begins with a convivial moment: a glass of coffee or mint tea and slices of bread with jam made with fruits from the garden. Then, the tasks to be done are collectively and easily decided. The collective work in Monlong allows for rapid transformation of the plot and lively discussions, and the objectives set are generally achieved during the day.

Connection to nature has been shown to reduce the risk of depression, anxiety, hypertension, and heart problems [14,15,16].

M > 45 years old looking for a job: “In the garden, I forget all and I’m in a bubble”.

W > 60 years old “I raised 6 children, I garden and I think of nothing else, it clears my head”.

A representative of a women’s association affirmed that: “The majority of women are single parents and life has weakened them, the gardening activity participates to personal reconstruction”. As a form of therapy, taking care of plants means taking care of yourself, thus regaining self-confidence.

D8 “Plants and people have the course of existence in common, they can be fragile but also very resistant”. The garden can be experienced as a daily or weekly regulator, where the negative effects would be absorbed by the earth, giving rise to creativity and journeys that contribute to personal fulfillment. One participant took part for psychic recovery: J8 “to be in shape, here is to have the feeling of not being the toy of events, but of living one’s own life”.

For some retired people, gardening acts as a replacement for professional activity, in order to maintain physical activity and frame their days. As a result, it can be identified as a “bridge over retirement,” allowing one to maintain social relations. It is an aid to the ability to accept change and the desire to project oneself. It also supports the definition of health, in terms of physical, mental, and social well-being.

M >55 years in business: “On Saturdays, after week, I garden to get away from it all, I experiment, create, grow plants from my home. I also plant flowers to promote biodiversity”.

3.2. Produce Healthy Vegetables: Agroecology Practices and Pollution Knowledge of Gardeners

For gardeners, the cultivation of vegetables allows them to taste good organic, local, and mature vegetables, including different varieties that one may not always be able to acquire. W > 40 years old “I harvested 32 beets which I keep in the sand, it allows me to have enough for the whole year, and I prepare the Borscht! it’s excellent”.

Affectivity attached to childhood memories was also found to persist: M > 65 years old: “I gardened at four years old with my father, until 22 years old. Then, in retirement, I needed to garden, according to the Arab proverb: old age which studies, writes in the sand and youth carves in stone”.

A high number of plant species and varieties were observed in the gardens, depending on the season, including tomatoes (cherries, beef heart, Bern rose, etc.), salad vegetables, broad beans, spinach, artichokes, beans, cabbage, carrots, potatoes, onions, leeks, aromatic plants, and so on. The yields achieved by some gardeners (according to harvest notebooks) are at the level of professional organic farms, as these gardeners spend time, observe, and act quickly in the case of disease or pest pressure. Therefore, in terms of quality, quantity, and variety, gardening activities enroll gardeners in a more sustainable food approach, from farm to fork and even beyond, including skills developed regarding the use of “ugly” vegetables and organic waste recycling.

In terms of raising awareness and collective risk management in gardens, the question of pollution was discussed at all four studied sites, considering the quality of air, soils, inputs (water, compost, straw) and, ultimately, the produced vegetables. Attention is paid to pollutants according to the histories of the plots and their environments, especially in the cases where factories or roads are visible from the gardens, as for the Monlong (waste incinerator) and Balma (bypass and metro line) sites. Regarding the observations, those gardeners with environmental and health risk concerns can be divided into three categories [9]: 1. preoccupied gardeners who mistrust institutions, 2. gardeners waiting for information to form their opinion, and 3. gardeners who wish to develop autonomy and their skills to act. In France, data are accessible through measurement networks and databases (e.g., RMQS for soils). For example, in Monlong, thanks to the sensors installed by the Regional Air Observatory (ORAMIP), the air quality is checked regularly. Analyses are also carried out on lichens (organisms without roots, which are thus dependent on-air quality and rainwater) collected within a radius of 2 km around the incinerator. Regular soil analyses carried out by the “Calligée” design office have led to the conclusion that the soil is of adequate quality for vegetable cultivation, even if various potential pollutant sources can be observed around the gardens; namely, the waste incinerator at 250 m, storage and use of radioactive products (ICPE subject to declaration) at 130 m, and storage of chemical products for the municipality of Toulouse at 100 m.

It was found that 70% of the gardeners would like to be able to find and understand information on the quality of vegetables, air, soil, or water used in gardens more easily. They are mostly interested (85%) when soil analyses are carried out on their plots. They trust the city a priori to provide safe spaces (75%) and some believe that, in the city, it is logical to be subjected to pollution: “Anyway, if you don’t eat it, you breathe it” (Monlong-J9). The influence of air quality on the quality of production in the collective gardens of Balma (bypass) and Monlong (incinerator) was therefore studied more precisely by the gardeners through participative scientific projects, which involved measuring total metal concentrations (Pb, Cd, Sb, As, Zn, and Cu) in topsoils (0–30 cm) and in harvested plants (salads or cabbage). In Balma, soils and plants were sampled in plots distinguished by their distance from the A62 road (various gardening plots: 203, 315, 201, 141, 320 and 504). An absence of impact on soil quality from the road (via comparison of the plots and values of the local natural geochemical background) was concluded. Moreover, soil Cd, Pb, As, and Sb concentrations and As for leafy plants were lower than the threshold values issued by the European regulation. The collaboration between researchers and gardeners through observations and experiments in the gardens promotes the appropriation of scientific data relating to the quality of the environment by the gardeners. This scientific knowledge reduces their anxiety and promotes their motivation to participate in projects that allow them to make informed decisions and actions.

The beginning of shared gardens emerged in Toulouse in 2006 with a double entry, comprising city policy and the management of green spaces. In 2019, in order to improve the efficiency of gardens in terms of public disposition, a meeting with social centers and gardeners was carried out with the aim of identifying indicators for evaluation of the social and environmental dimensions of shared gardens.

Table 4. Criteria (C) and indicators (I) to assess: “Creation and/or densification of social ties,” “Individual skills and resources,” and “Social and environmental quality of the territory.”

Creation and/or Densification of Social Ties Criteria	Indicators
C1. Interpersonal relations between gardeners and gardeners/local residents	I1. Nature, evolution, and frequency of exchanges: loans of tools, seeds, knowledge, services, etc. I2. Number of convivial and shared events: meals, preparation of dishes, etc. I3. Expansion of the network, considered as the percentage of gardeners who feel that they have expanded their network thanks to the garden, in terms of acquaintances, friends, and inhabitants.
C2. Lasting interpersonal relationships	I1. Continuation of contacts.
C3. Feeling of belonging to a group	I1. Analysis of the discourse from “I” to “we.” I2. Compliance with the rules.
C4. Diversity and intergenerational, intercultural, and gender diversity	I1. Proportion of ages, sexes, origins, socio-working categories. I2. Nature (typology) of exchanges between groups.
C5. Solidarity	I1. Investment of time to help/transfer of skills/donation of knowledge.
Individual “Skills and Resources” Criteria	Indicators
C1. Improvement of the domestic economy	I1. Evolution of purchases: increase in ethical purchases (seasonality, origin, etc.)
C2. Development of individual know-how	I1. Proportion of people expressing greater know-how: gardening, cooking, healthy cultivation, moving around alone, etc.
C3. Improvement in eating habits	I1. Proportion of people declaring an increase in the consumption of fruit or vegetables/diversity of fruits and vegetables consumed.
C4. Development of the practice of physical activity	I1. Frequency and regularity of visits to the garden. I2. Proportion of gardeners declaring that they practice more physical and/or sporting activities outside the garden or outdoor outings.
C5. Citizen involvement	I1. Participation in events organized in and outside the neighborhood. I2. Degree of involvement of participants in the process of building gardens: nature, frequency and evolution of participation, community, etc. I3. Number and type of initiatives by gardeners on new actions.
C6. Development of pleasure in creating, sharing, well-being	I1. Proportion of people expressing a feeling of pleasure and/or well-being: linked to taste, creativity, sharing, etc.
“Social and Environmental Quality of the Territory” Criteria	Indicators
C1. Pacification of public space	I1. Reduction of incivility (degradation, conflicts) in the gardens and surrounding areas.
C2. Respect for the environment	I1. Frequency and practice of selective sorting. I2. Energy savings: water, electricity. 13. Frequency and type of use of soft transport.
C3. Offer of healthy products	I1. Use of organic products.
C4. Enhancement of the neighborhood’s image	I1. Number of visits by groups from outside the neighborhood, number and type of events organized in the gardens.

lists the corresponding criteria (C) and indicators (I), which are used to assess “Creation and/or densification of social ties,” “Individual skills and resources,” and the “Social and environmental quality of the territory.” Observations in the gardens and surveys in 2019, conducted face-to-face in the four shared gardens (29 interviews) and by email to members of the shared gardens in Toulouse (44 completed questionnaires), were carried out to assess the efficiency of the shared gardens in social and environmental aspects. This study led to the following conclusions: the users of shared gardens in Toulouse are mostly over 60 years old, and have mostly been living alone in Toulouse for more than 10 years. They are satisfied with the shared garden they frequent, finding it “well-equipped” and to have “a pleasant atmosphere.” However, 50% encountered difficulties in using the garden and reported requiring better supervision and maintenance by the Town Hall and efforts on equipment. The users of the shared gardens reported developing more healthy eating habits and a strong interest in protecting the environment. According to the gardeners, the two main interests of a shared garden for a neighborhood are to promote more ecological practices and to encourage human exchanges. The values and ideas spontaneously cited to describe the shared gardens included: sharing, exchanges, respect for the environment, conviviality, fraternity, solidarity, living together, consuming differently, pleasure, meeting, ecology, and nature in the city. “The shared garden brings gaiety and exceptional biodiversity. It makes our neighborhood more pleasant!” (Monlong-G15).

Since 2021, a new charter for shared gardens in Toulouse was introduced: “nature in the heart of neighborhoods” (Town Hall of Toulouse, 2021). The municipal team decided to double the number of gardens shared in neighborhoods by 2026. To promote their harmonious and coherent development, this Toulouse Charter aims to explain the specificities of shared gardens in Toulouse, including consultation standards, citizen participation, and ecological practices. The values and collective commitments of the shared gardens, according to the charter, are as follows: 1. Conviviality. 2. Respect for the environment: “The gardeners cultivate the land while respecting the environment, using natural gardening techniques, crop rotation, introduction of diversified plants, mulching… The shared gardens are laid out in an eco-responsible approach, respectful of natural resources and soil life. Develop the gardens with a sustainable approach with an optimization of resources. Create favorable conditions for the reception of biodiversity. Raising residents’ awareness of environmental issues.” 3. Improvement of the living environment: “The resident-gardeners contribute to enhancing the living environment of their neighborhood…Diversify and beautify the landscapes of urban areas…” 4. Well-being: “Gardening contributes to the well-being, promotes contact with nature and allows access to quality, healthy and varied food at a lower cost. Do not use products harmful to health. Diversify crops over the seasons.” 5. Citizenship and secularism: “A shared garden project allows inclusive and open mobilization. It empowers the actors: the practices are participatory and collective in the design and management of the shared garden. Involve the inhabitants in the life of the garden and in the dynamics of the district. Federate a collective and participatory approach…” 6. Transmission and Education: “Educate on the environment to support ecological transition and sustainable development. Educate and sensitize the various audiences to respect for the environment. Organize educational and recreational activities. Sharing our experience in order to develop curiosity and know-how.” 7. Virtuous development: “The shared garden ensures a balance between ecological, cultural and social issues. It provides knowledge to fully understand our relationship and interdependence with the ecosystem. Optimize and preserve the resources made available. Recycle waste and materials. Respect and protect natural environment.” 8. Respect for the commitments defined in the charter: “The garden manager undertakes to respect the values specified in the charter, within the framework of the partnership agreement signed with the Town Hall which accompanies it in its action to meet the expected.”

4. Discussion Concerning Global Health and Agroecology in the Gardens

4.1. Empowerment in Gardens for One’s Health Is Favored by Collective Approaches

Exchanges, mutual aid, and solidarity [17] represent promising strategies for engaging gardeners—and, more broadly, the users of collective gardens—in ecological transitions [18]. Autonomy is also a fundamental principle of agroecology, which responds to issues of social justice [19,20]. Moreover, collective action promotes agroecological transition at the landscape scale [21]. The four considered collective garden sites are strongly enriched with biodiversity and illustrate the creativity of their users. The management of agroecological infrastructure and crops at the landscape scale enables the regulation of crop pests [22,23]. Landscape configurational heterogeneity—that is, mixing of the three strata of vegetation and flower areas—favors psychological restoration when perceived by visitors [24]. Sensitive experiences in the interactions between gardeners and their gardens in Occitania have been studied, and the authors concluded that through the bonds that are generated—both in the body and the mind—the sensitive experiences in gardens strengthen the freedom and creativity of gardeners, leading to positive impacts on health [25]. According to the INSEE (population projection for 2060) “until 2035, the proportion of 60 years aged-people or over will increase sharply;” therefore, preserving the health and morale of seniors and controlling expenditure related to population aging are important public issues. Available epidemiological studies have indicated that gardening activities delay functional decline (e.g., ventilatory capacity, muscle strength, and cardiovascular output) and chronic diseases in seniors. Moreover, gardening activities have also been shown to improve mental health.

4.2. Agroecology and Transmission in Gardens, Particularly on Soil Care

The garden is a life-size workshop for reconnecting with nature, reinforcing the link between plants and the seasons, as well as helping individuals to learn to respect life in all its forms and strengthening intergenerational exchanges. Adjusted relations between gardeners were observed, which were translated through mutual aid, respect, exchanges of knowledge, donations, and (sometimes) emulation. Urban community gardens can be particularly structurally complex and harbor a diverse range of nesting and food resources for pollinators [1]; for example, long grasses benefit butterflies and are crucial in reducing the loss of biodiversity [26]. Recent research works have concluded the importance of developing communication towards public spaces to promote environmental education, thus guaranteeing informed participation in meetings [4,5]. These urban agriculture projects strengthen the social dynamics of greening practices, with multi-stakeholder consultations typically consequently inducing increased needs for knowledge, training, skills, and regulations on these environmental and health-related aspects in order to optimize ecosystem services and the resilience of cities [27,28]. A majority of respondents saw their parents and/or grandparents gardening, but did not practice then, eventually learning in the context of the collective gardens. Access to a green space allows them to gain experience and benefit from the advice of other experienced gardeners:

“It’s a good experience in the garden; if I was at home, I would only have what I wanted to believe books, the internet… I wouldn’t have Anne next to me telling me “there it’s ready you can pick up… or there, no need what you let grow, it’s not raspberries but brambles [laughs]”.

(Simon, 33 years old, Balma)

Socialization in shared gardens is a major issue, influenced by the historical and sociopolitical context. Family socialization in gardening often influences the decision to join a shared garden: the majority of people questioned had seen their (grand)parents gardening, such as D. Dupouy, who decided to create the Tourn’Sol gardens because his grandfather took him to a collective garden in Paris.

“These allotment gardens, it was an idea since a long time. I had been able to take advantage of a small garden in Paris with my grandfather in the family garden.”

Regarding environmental recommendations, chemicals have been nationally banned in gardens since January of 2019, promoting the need for alternatives to synthetic phytosanitary products. In Balma, this ban has been in place since 2015. In the gardens of Tournefeuille, this ban was effective following discussions with the gardeners, revealing the need for participatory democracy to change regulations. In the shared gardens of Blagnac, the ban dated from the creation of the gardens. In these gardens, regulations concerning the tiller used to work the land have evolved. In the gardens of Tournefeuille and Balma, it has not been banned; however, the managers promote the grelinette as alternative tool reducing soil structure perturbation. With regard to reducing irrigation in Balma, opening and closing times for the taps limit the consumption of water while, in Tournefeuille, gardeners are limited to 500 L per day through the provision of tanks which are filled each night with water from a retention basin created for the gardens. In addition, a large amount of information is available to gardeners on the associations’ websites, including charters, internal regulations, and so on. Although social and ecological issues were observed in all four plots, there were differences in the gardens studied with regard to the provided instructions and injunctions. In Blagnac, collective gardens are considered “as a showcase of environmentally friendly gardening,” and the town hall is proactive in developing ecology in the gardens. In Tournefeuille, children can also take a walk in the “Butinopolis” trail created by volunteers, in which they can see the life underground thanks to a terrascope. In Blagnac, the association of Caouecs allows children from nursery schools to learn about gardening by soliciting all the schools in the city. On the other sites, school outreach activities also exist, but in a more ad-hoc manner due to lower involvement of gardeners. As illustrated in Figure 3, spaces are made available to school groups.

Climate change influences production in gardens and induces changes in practices. René (67 years old, volunteer in charge of green spaces at the Périole gardens in Balma) now uses the lunar calendar to anticipate the right times to plant crops, while remembering the advice of farmers about “key dates.” The effects of such warming can be seen in the possibility of more easily cultivating “exotic” species, such as chayote from Reunion Island. “Here it’s Chayotte, it makes small fruits, but after that it looks like pears. I experienced this in Reunion, and when I saw that it was happening and I put three feet. Oh well now [laughs], the climate will become the same…” (Fabienne, 47 years old, Balma).

Strategies are gradually being implemented in collaboration with the technical services of the town hall and researchers to achieve ecologically efficient developments. For example, the ban on eco-toxic products promotes biodiversity and overall health in the garden. Complementary agroecological infrastructures can be observed in the collective gardens, including permanent grasslands, grass strips, hedges, isolated trees, and wetlands. The town hall of Toulouse has a policy of preservation and enhancement of trees and wetlands in gardens; for example, in the Monlong park, hedges and ponds are set up in collective gardens to encourage the presence of auxiliary insects such as carabids thanks to the supply of food and habitats. Ladybugs—which are very effective for the biological control of aphid invasions—are fond of wetlands, as are frogs and tadpoles which eat insect larvae and slugs.

Soil is placed by gardeners at the center of agroecological practices in their gardens [6,10]. Soil care was found to be developed throughout specific gardening practices on all four sites, such as the practices of composting and using plant covers in order to promote carbon storage [29]. “Today it’s different, we cover the ground, we put mulch, we put shredded material, we feed the land with compost, manure instead of chemical fertilizers. It is not at all the same spirit as before. […] we are lazy because we no longer work the soil, but we promote earthworm’s bioturbation; it’s new logic.” (Tournefeuille-A). Many gardeners planted broad beans, mainly because they improve the soil through nitrogen input. “In the first spring, I plant beans and peas to enrich my soil with nitrogen, because most of my crop is plants that need nitrogen. Whether it’s squash, cucurbits, zucchini, cucumbers, and even tomatoes for that matter, these are plants that need a lot of nitrogen.” (Romuald, 37, Tournefeuille gardens). In Tournefeuille, surveys of practices among gardeners (in the field and by email: 73 gardeners) revealed variable practices concerning compost, manure, rototiller, and mulching. The soil analyses made it possible to conclude that there was no metal pollution and that the soil was generally fertile, even if significant differences in organic matter content (between 4% and 15%) were observed in connection with the practices. According to the president (D. Dupouy), who is heavily involved in development and events: “there has been a strong evolution since 2005 in the profiles of gardeners, today we have more families interested in ecology and the soil. These gardeners want to teach children about nature and safe food. We observed in fifteen years, an evolution from gardeners mainly interested by the production, to gardeners more committed to the environment and health.” The results of the agronomic studies were communicated to the gardeners, who took the opportunity to ask many questions to ensure that the soil is healthy. In Tournefeuille: “Few gardeners use the tiller, because we had participated in earthworm research studies and we saw that those who used tillers no longer had earthworms.” (Tournefeuille-A).

In Monlong, the soil texture results thanks to the so-called “boudin” field test made it possible to classify the soils as sandy loam to medium loam, with sometimes a greater presence of clay (which can promote water storage). Texture and pH influence aggregate stability (structure), as well as water and nutrient retention. Low effervescence with acid indicates that the soils of the gardens at Monlong are low in carbonates, and no significant soil pollution with metals was detected.

In Blagnac, pH, the cation exchange capacity, and the contents of major and trace elements were analyzed in various gardens to assess soil fertility, at the request of the gardeners. In accordance with the observations and knowledge of the gardeners, these analyses revealed an average agronomic state, with bioavailability of nutrients and a low CEC (related to the presence of silt and the low organic matter content); in particular, between 9 and 20 cmol+/kg. The pH is generally basic (8–8.7), which is in accordance with the knowledge that the source rock of the soil is carbonated. These results confirmed the gardeners’ impressions of quite low soil fertility and the interest in adding organic matter. No trace metal pollution was observed within the grounds of the gardens, in accordance with the site’s history. The gardens of Blagnac are in the floodplain of the Garonne. The pedogenesis of these soils is therefore influenced by the alteration of carbonate rock, as well as by fluvial inputs (silty alluvium) during successive floods. Two 60 cm-deep profiles were obtained in the field, the first to the west of the gardens and the second to the east, closer to the Garonne (Figure 4).

Soil analyses in Balma showed variations for: (i) CEC (we/kg) between 126 and 300; (ii) water pH between 7.6 and 8.5; and (iii) clay between 20 and 50%. Around 70% of gardeners reported using a hand tool to till the soil before sowing; 40% of gardeners sowed broad beans, phacelia, or mustard as a plant cover during the winter; 75% of gardeners surveyed made and used compost. The gardeners used manure and natural organic fertilizers (e.g., horns, dried blood, guano), with 85% using manure from the equestrian centers of Pins-Balma and some obtaining their supplies directly from cattle breeders. More than 80% of gardeners noticed an improvement in their soil after these inputs. The most frequently found weed species include quackgrass, thistle, dandelion, ragwort, and bindweed, and 82% of gardeners reported removing weeds from their garden by hand and sometimes also mechanically. The main pests observed were slugs, beetles, aphids, and rabbits, and the main diseases observed were downy mildew, powdery mildew, and rust. To protect plants, gardeners reported using biological products (e.g., copper-based, black soap, or natural essences) and were encouraged to use reduced doses.

Of the gardeners questioned on the four sites, 95% claimed to support soil biodiversity. Increasing concern regarding living soil and global health has also been highlighted in a recent review of the literature on urban gardens [30]. After the soil observations and analyses, the gardeners concluded that: “in gardens the soil is directly visible, we can touch it, work it, plant our future food there, so we have an interest in taking care of it, in not contaminating it with plastics, chemicals or other pollution. I’m very happy when I see earthworms, different insects that live in my garden and seem to be in good shape! It’s reassuring for me” (Tournefeuille, G22). In the gardens of Balma, in addition to certain volunteers who share their knowledge of biodiversity, a professional photographer documents the fauna and flora in images. These photos are available on the website of the association of shared and family gardens of Garonne, as well as on the website https://balma.biodiv.fr/spip.php (6 January 2025), on which everyone can participate in this biodiversity census through sharing their observations. In Tournefeuille, in addition to the Bunipolis place, the diversity of plant and animal species and soil life are presented with educational panels, as well as an observation device for the galleries revealing biological activities within the first few centimeters underground. Furthermore, workshops on the characteristics and reactivity of the soil are frequently organized in the gardens in collaboration with scientists; for example, those from Réseau-Agriville (see Figure 5).

5. Conclusions and Perspectives

Key findings: Through its multiple dimensions, health is an efficient vector to promote agroecology in collective gardens. Natural gardening in a shared plot allows for experiences which foster care for living organisms and acts for the health and protection of the environment. The results of this long-term study revealed that the evolution of practices depends on transmission—in particular, in an “informal” mode—which reinforces the idea that collective experimentation facilitates social relations and ensures the dissemination of agroecological principles. Urban collective gardens can thus be analyzed as sociotechnical devices, guiding practices according to standards and values. Through conveying ecological ideals via technical sheets, advice, and participation, managers can promote the normative work of the system. The opening of debates and the existence of controversies, which can sometimes lead to conflicts between gardeners, are considered as part of the democratic process of a public system and make it possible to change social conventions in collective gardens.

Gardening activities promote connections between gardeners with their bodies and nature. The four studied collective gardening sites in Toulouse presented specificities concerning the main goals for gardeners, in accordance with their history, organization, and location, including aspects such as health, production of vegetables, social interactions, and soil care. Soil health is a major concern not only for production, but also for preservation of the environment. The ban on synthetic phytosanitary products has reinforced interest in soil care and attracting auxiliary insects for biocontrol purposes. The presented results highlight the roles of urban gardens in promoting global health through agroecological practices and soil care, with consequential effects on dietary habits.

In perspective, increasing the networking capacity of collective gardens, the dissemination of ecologically efficient practices (e.g., those with cultural associations), promoting living soils, and enhancing the synergies between the involved actors (e.g., gardeners, elected officials, researchers, industrialists, etc.) are all avenues that have been investigated by researchers in conjunction with Toulouse city thanks to funding provided by National Research Agency-Sciences with the Society. In addition, the evaluation of the policies implemented by the city and the metropolis of Toulouse, in terms of support for urban collective gardens, will be carried out by mobilizing other tools such as budget analysis, beyond the statements of key actors, as well as benchmarking with respect to other cities. Gardens—whether family, shared, or educational—now cover several thousand hectares in France, thus promoting local food production, experimentation, education, and awareness-raising. Faced with ecological, climatic, and health challenges, agroecology represents a promising alternative for re-thinking these spaces in a sustainable manner, particularly through the restoration and preservation of soil health. More broadly, such principles help to foster regional resilience, as the implementation of agroecological approaches in gardens is reproducible. This is why supporting urban collective gardens must be included in local and national public policies promoting the agroecological transition. However, the sustainable development of urban gardens requires transdisciplinary policy (agronomy, urban planning, environment, etc.) for managing the use of land according to its quality, which is gradually being developed but is not yet operational.