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Urban community gardens are socio-ecological spaces, in which the conservation of pollinator diversity in cities can be directly promoted through conservation gardening. However, there is a lack of insights into how practical knowledge of gardeners can be combined with scientific findings in order to develop evidence-based and practice-oriented guidelines for insect conservation interventions. In a co-creation process, we facilitated three workshops with community gardeners from Berlin and discussed research methods and results from four years of ecological research on the relationships between pollinators and garden features. Subsequently, we performed a qualitative content analysis to identify critical adoption barriers and learn from previous experiences of the gardeners. Our preliminary results revealed the gardeners’ great interest in understanding the scientific process as well as their high motivation to integrate new information in their own knowledge. Therefore, we think that co-creation has high potential for initiating change as it includes relevant stakeholders at an early stage of the transformation process.

Urban areas can be both detrimental for pollinators or function as suitable habitats, depending on the land-use type, the urban context and the pollinator group in focus. Urban green spaces, including gardens, parks or cemeteries can provide essential resources for a wide range of pollinator groups, like wild bees, hoverflies and beetles. Urban community gardens can be particularly structurally complex and harbour a diverse range of nesting and food resources for pollinators. However, we know little about how garden features may vary with the urban context of gardens and which specific garden features can increase the abundance of pollinators in general and of different pollinator groups.Over two summer seasons, we recorded garden features and pollinators using flower observations in 33 urban community gardens in Munich and Berlin, Germany. We examined how garden features differ amongst urban community gardens from three urbanisation categories, and analysed the effects of garden features such as floral and nesting resources and landscape imperviousness (as indicator of urbanisation) on pollinator abundance, richness and diversity.In more urbanised gardens, flower richness and bare substrate were less prevalent. Flower richness was positively correlated with overall pollinator abundance, richness and diversity as well as with the abundances of all pollinator taxa excluding beetles. Landscape imperviousness was negatively correlated with hoverfly and beetle abundances. Hoverflies also decreased with increasing bare substrate and wasp abundance decreased with increasing deadwood availability. Our findings highlight the important role of flower richness for insect conservation in urban management and show that pollinator taxa react differently to garden features and urbanisation. To support pollinating insects, gardeners can increase flower richness, especially in highly urbanised areas.

Abstract With the boom in urban living has come a boom in urban gardening. In particular, urban community gardening is an increasingly popular form of horticultural production, community involvement and connection to nature. Through the establishment and management of community gardens, biodiversity can flourish, with community gardens as ‘hotspots’ of flora and fauna within the urban matrix. Gardeners can deeply connect with the natural elements of gardens and thus learn about and gain appreciation for the natural world. Such interactions can combat the loss of nature experiences in cities. Despite their benefits for nature and for people, community gardens are threatened ecosystems as often temporary fixtures in city landscapes due to lack of land tenure and policy protection. In this perspective, we recognize community gardens as an important ecosystem in urban conservation and argue for the defence of urban community gardens by city policy. We formalize this activity and the value of these ecosystems with scientific evidence from ecological and social‐ecological research in 39 community gardens in Berlin and Munich, Germany. Although our data reveal that these gardens support large amounts of biodiversity and catalyse human‐nature connections, a lack of comprehensive documentation of social‐ecological benefits at the city level can make community gardens vulnerable to urban planning threats; we have seen losses of multiple research sites in the last 4 years of biodiversity research. Policy implications: To protect community gardens now and for future urban generations, we call for systematic and comprehensive data collection on community gardening activities and policy support for these urban ecosystems. Some cities are starting to do this and this can be scaled out. We argue for the recognition of urban community gardens as a physical land use and also of the gardeners themselves as important habitat managers and stewards of urban biodiversity. Read the free Plain Language Summary for this article on the Journal blog.

ABSTRACTGlobal challenges around biodiversity loss, climate change, and public health are heightening the importance of urban green spaces for supporting ecosystem services and human wellbeing. Trees, parks and forests integrated across cityscapes are proposed strategies to combat climate change and promote human health for current and future cities. This is true for small urban green spaces, perhaps just < 1 ha in size. Depending on their structure and size, these spaces can provide structural vegetation complexity, promote species diversity, regulate temperatures and offer human thermal comfort. These spaces also provide recreation opportunity, nature experience, sense of belonging, and restoration to people. As cities densify, it is crucial to understand where these dimensions intersect in theory and practice to design and manage small green spaces in particular, as these systems may be easier than large green spaces to implement in urban planning. In this paper, we narratively review known biophysical and ecological properties of green spaces that support biodiversity, promote temperature regulation and climate resilience, and may ultimately benefit residents’ health through different use activities and multisensory experiences that promote restoration and wellbeing. Furthermore, we review how stakeholder engagement and participatory processes can guide equitable green space provision and design, and we use case studies and our own research as examples. In doing so, this paper aims to further the understanding of the social-ecological importance of small urban green spaces and calls for inter- and transdisciplinary research that generates insight to design, manage and protect these places in a changing climate.

City street trees are prominent features of urban green infrastructure and can be useful for climate change adaptation. However, street trees may face particularly challenging conditions in urban environments. Challenges include limited soil and space for growth surrounded by sealed surfaces, construction that damages roots, poor pruning and management, and direct vandalism. All of these challenges may reduce the capacity of street trees to provide social-environmental benefits, such as attractive landscapes, shading and cooling. Thus, street trees need specific care and resources in urban environments. In this perspective article, we call for a conversation on how to improve the conditions for city street trees. While research has broadly investigated street tree mortality and vulnerabilities, the social perspective may be missing, one that also involves the actions and care by human inhabitants. Here we share perspectives on current management options and discuss from a social-ecological perspective how these can be extended to involve urban residents.

Pollination is a vital ecosystem service in urban agriculture. Yet the environmental drivers of both crop and wild plant pollination in urban agroecosystems are still not well understood. Pollination experiments involve the manipulation of pollen transfer between plants, for instance, to study the effects of pollinators on fruit and seed production (pollination service). In this study, we conducted a pollination exclusion experiment using four experimental plants: two cultivated plant species, strawberry (Fragaria x ananassa) and chili pepper (Capsicum frutescens), and two wild plant species, buttercup (Ranunculus acris) and clover (Trifolium pratense). We placed experimental plants for over 20 days in 13 urban community gardens in Munich, Germany. We compared fruit and seed mass between “open” and “bagged” flowers and tested the effect of biotic factors (floral resources and pollinator diversity) and abiotic factors (urbanization, microclimate) on pollination service (fruit and seed mass) on the experimental plant species. For the two cultivated plants (F. ananassa and C. frutescens), we found that fruit and seed mass were both positively correlated with temperature and pollinator diversity. For the two wild plants (R. acris and T. pretense), we found that floral abundance was negatively related to R. acris seed mass but was positively related to T. pratense seed mass. In summary, we found that biotic and abiotic parameters affected the plant species studied here in different ways, suggesting that there may be synergies and trade-offs in what factors promote the overall pollination of urban plant communities. Our results suggest that gardeners can potentially increase the pollination services on certain garden plants by providing floral resources for pollinating insects.

Gardening offers a range of benefits, from food production to social connection to improved mental and physical health. When COVID-19 struck, interest in gardening soared, but it was unclear whether and how gardens would deliver these benefits in the midst of a global pandemic. We analyzed survey responses from 603 home and community gardeners across California, collected between June and August 2020, to assess trends in pandemic gardening. Gardeners highlighted the importance of gardens as therapeutic spaces where they could escape the stress of the pandemic, and as safe outdoor places for socializing. The study also revealed people’s concerns about food supply, along with an accompanying interest in growing their own food to increase food security and self-sufficiency. The pandemic posed challenges for home gardeners, though, with 62% struggling to access gardening supplies. These findings suggest the importance of providing garden space, resources and support, especially to those populations with the least access to green space, so that gardens can serve as resources to improve community health, food security, and resiliency during future disasters.

The urban heat island (UHI) effect remains a major threat to society as cities densify and sprawl. Urban greening through local to landscape management is a proposed strategy to combat UHI and improve environmental justice in city neighborhoods. For example, urban community gardens are multifunctional green spaces that play an important role for biodiversity and for civic engagement. But the role of urban gardens in urban cooling and relieving UHI remain unclear, specifically how temperatures fluctuate within gardens in relation to garden management factors and city landscape context, and how this relates to urban heat in city neighborhoods. We investigated diurnal and nocturnal temperature ranges, and daily maximum and minimum temperatures in 18 urban gardens over the peak of the summer agricultural growing season. We then analyzed how temperatures were correlated to local land cover factors within the garden, to surrounding landscape imperviousness at various spatial scales, and to environmental justice indicators (stressors) of garden neighborhoods. We found that nocturnal temperature range is negatively correlated to landscape imperviousness, and that the relationship decreases in strength with increasing spatial scale. This result supports the importance of evapotranspiration processes of surrounding green areas for nocturnal cooling. Some local land cover factors were important for temperatures, indicating heating or cooling management mechanisms from within urban gardens. Finally, the mean number of environmental stressors in neighborhoods negatively related to temperature variation. The results of this work can inform resource use and crop selection in urban agriculture, as well as how temperature-related ecosystem services of gardens relate to environmental justice of city neighborhoods.

The recent COVID-19 pandemic has changed the way people live in an unprecedented way. This includes severe impacts on people's health and wellbeing such as stress, reduced physical activity and loneliness due to confinement. In parallel, people had to find ways to secure their food, with fresh food especially scarce in some regions due to lockdowns and restricted flow of goods. As in previous massive crises, the practice of home food gardening seemed to have increased during this pandemic. Yet we largely do not know which parts of society took to home food gardening, in which urban setting home food gardening was practiced, and to which extent this practice contributed to people's daily livelihoods during the pandemic. In this case study we explore (a) who practices home food gardening, (b) the garden characteristics, and (c) the main perceived benefits and barriers bound to home food gardening during the pandemic. We set up an online questionnaire targeted at the population of Santiago de Chile, for which we received 305 responses. Our results clearly show that the possibility of being in contact with nature and feeling less stress through practicing home food gardening were the most significant perceived benefits, while lack of or inadequate space to garden and limited knowledge on home food gardening were the main barriers. These findings highlight for the specific context of a metropolitan region in South America that access to gardens and green space could contribute to a just urban society. Likewise, the practice of home food gardening can be a relevant tool to cope with the adverse consequences of the pandemic by informing public initiatives to promote healthier lifestyles during this and future crises contexts and also in the awaited “ordinary” times.

Agroecosystem management influences ecological interactions that underpin ecosystem services. In human-centered systems, people's values and preferences influence management decisions. For example, aesthetic preferences for 'tidy' agroecosystems may remove vegetation complexity with potential negative impacts on beneficial associated biodiversity and ecosystem function. This may produce trade-offs in aesthetic- versus production-based management for ecosystem service provision. Yet, it is unclear how such preferences influence the ecology of small-scale urban agroecosystems, where aesthetic preferences for 'tidiness' are prominent among some gardener demographics. We used urban community gardens as a model system to experimentally test how aesthetic preferences for a 'tidy garden' versus a 'messy garden' influence insect pests, natural enemies, and pest control services. We manipulated gardens by mimicking a popular 'tidy' management practice-woodchip mulching-on the one hand, and simulating 'messy' gardens by adding 'weedy' plants to pathways on the other hand. Then, we measured for differences in natural enemy biodiversity (abundance, richness, community composition), and sentinel pest removal as a result of the tidy/messy manipulation. In addition, we measured vegetation and ground cover features of the garden system as measures of practices already in place. The tidy/messy manipulation did not significantly alter natural enemy or herbivore abundance within garden plots. The manipulation did, however, produce different compositions of natural enemy communities before and after the manipulation. Furthermore, the manipulation did affect short term gains and losses in predation services: the messy manipulation immediately lowered aphid pest removal compared to the tidy manipulation, while mulch already present in the system lowered Lepidoptera egg removal. Aesthetic preferences for 'tidy' green spaces often dominate urban landscapes. Yet, in urban food production systems, such aesthetic values and management preferences may create a fundamental tension in the provision of ecosystem services that support sustainable urban agriculture. Though human preferences may be hard to change, we suggest that gardeners allow some 'messiness' in their garden plots as a "lazy gardener" approach may promote particular natural enemy assemblages and may have no downsides to natural predation services.

Climate change is impacting the ecological, social and technological aspects of urban gardens. Gardens experience threats (e.g., water scarcity) but are also responding through adaptation strategies (e.g., selecting drought-resilient plants). A synthetic overview of how urban gardens are affected by climate change and responding to climate change is unclear. Here, we systematically reviewed articles and book chapters published in the last two decades (2000–2022) to illustrate the relationship between climate change and urban gardening. From 72 documents analyzed with Nvivo Software, we found that there has been an increase in academic publications. Universities from the US (14) and Germany (9) universities are the dominant producers. Evidence shows that climate change can have negative impacts on cities, people and urban food. Suggestions on how to build the adaptation capacity of urban gardens include collecting rainwater, changing plant selection, changing planting times, applying vegetative cover on the soil and other practices. For cities, community and allotment gardens are helpful for adaptation, mitigation and resilience. This includes the capacity to regulate the microclimate, to reduce urban heat island effects and to buffer urban floods, the power to capture carbon, the ability to create social networks and other socio-environmental benefits for urban climate planning.

During the COVID-19 pandemic, many countries experienced something of a boom in interest in gardening. Gardens have long been considered as refuges into which we retreat to escape various struggles and challenges. In this study we examine the characteristics and functions of the garden as a refuge during the period of increased garden interest associated with the COVID-19 pandemic. Analysis of qualitative results about garden experiences from 3,743 survey respondents revealed intertwining garden and emotional geographies. Utilising non-representational and therapeutic landscape theories, we found multifarious and heightened experiences of non-material aspects of gardens; that is, the sensory and emotional aspects. People experienced, for example, a sense of joy, beauty, and reassurance, a greater attunement to the natural world and an increased sense of nature connection than they had at other times: birds felt louder. These heightened sensory and emotional experiences had therapeutic benefits, across age and geographical spectrums, during these difficult times. This research improves our understandings of the positive potential of non-material aspects of gardens in the creation of therapeutic landscapes in and beyond COVID-19.

Community gardens are important urban green spaces with a variety of social and ecological benefits, one of which is access to healthy food. Similar to rural agriculture, the quantity and quality of the food produced can be compromised by pest damage. In fact, many urban gardeners report crop damages caused by vertebrate and invertebrate pests. Yet, because the food produced in community gardens is mostly for self-consumption and thus not under market quality standards, the damage thresholds and the point when gardeners perceive a pest problem and how they decide to manage it, may greatly vary from gardener to gardener. Here, we investigated how socio-demographic factors and experience affect whether gardeners report having a pest problem and which pest management practices they use. We surveyed 187 gardeners from 18 different urban community gardens in three counties in the California central coast, USA. We also collected information about gardener socio-demographic factors (age, gender, ethnicity), as well as education, and years of experience in agriculture. The majority of gardeners reported having pests in their plots but their ethnicity, the amount of time they spend in the gardens, and whether they work in agricultural-related employment or not influenced the likelihood of reporting pests. We found that the majority of gardeners use curative, non-synthetic practices for managing pests, but that some use preventive practices and some don't do anything to control pests. The likelihood of using practices that are curative depended on gardeners' ethnicity, the amount of time they spend in the gardeners, and their gender. Our results suggest that the agricultural knowledge of urban community gardeners and the practices they use varies greatly and that, in order to be successful, extension programs may need to take this diversity into account when promoting the agroecological paradigm in urban agricultural (UA) systems.

Abstract Biotic and abiotic factors at local to landscape scales influence insect pest and disease dynamics in agricultural systems. However, relative to studies focused on the importance of these drivers of crop plant damage in rural agricultural systems, few studies investigate plant damage from herbivore insects and plant diseases in urban agroecosystems, and consequently, most urban farmers lack knowledge on crop protection tactics. Here we use three common crop species within urban agroecosystems (community gardens) distributed across an urban landscape as a model system to ask how local, landscape, and microclimate factors relate to herbivore and disease plant damage. We hypothesized that plant damage would be lower in gardens with greater local vegetation complexity, landscape‐scale complexity, and less variable temperatures, but that the importance of factors is species‐ and damage‐specific. By measuring Brassica, cucurbit, and tomato insect pest and disease damage across the growing season, we confirmed that the importance of factors varies with crop species and by damage type. Both local complexity factors (e.g., number of trees and shrubs) and landscape complexity (percent natural cover in the landscape) relate to lower incidence of herbivore and disease damage on some crops, supporting our prediction that habitat heterogeneity at both local and landscape scales lowers plant damage. Greater temperature variability related to higher disease damage on tomatoes linking microclimate factors to disease prevalence. Yet, local complexity factors also related to higher incidence of plant damage for other crop species, indicating variable species‐level impacts of local management factors on plant damage. By measuring the abundance of fungus‐feeding lady beetles (Psyllobora) on cucurbits, we confirmed a strong association between natural enemies and powdery mildew. We provide a case study on how changes in local to landscape‐scale factors relate to plant damage in urban agroecosystems and suggest how urban farmers and gardeners can apply this ecological knowledge to improve sustainable urban food production.

The conservation of pollinators requires social understanding to catalyse restoration action. Citizen science (CS) is discussed as a way to promote interest and action for pollinating insects. Yet, the drivers behind pro-pollinator behaviour are largely unclear, especially in urban areas. To better understand public engagement in pollinator conservation, we studied urban community gardeners’ identity, nature-relatedness, emotions, and attitudes toward pollinators and their intentions to get involved in pro-pollinator behaviour in their gardening practice. We surveyed community gardeners in Berlin and Munich, Germany, some of which were participating in a citizen science project. In this scientific study, we created four different sets of generalized linear models to analyse how the gardeners’ pro-pollinator behaviour intentions and behaviour were explained by socio-psychological factors. The responses of 111 gardeners revealed that gardeners that were fascinated by pollinators, held positive attitudes and felt joy about seeing pollinators reported intentions to protect or support pollinators, suggesting that fascination and joy can be harnessed for research and conservation on pollinators. Similarly, joy about seeing pollinators predicted participation in the CS project. We believe that CS may represent a pathway through which urban residents may become key actors in conservation projects within their nearby greenspaces.

Landscape connectivity is a critical component of dynamic processes that link the structure and function of networks at the landscape scale. In the Anthropocene, connectivity across a landscape-scale network is influenced not only by biophysical land use features, but also by characteristics and patterns of the social landscape. This is particularly apparent in urban landscapes, which are highly dynamic in land use and often in social composition. Thus, landscape connectivity, especially in cities, must be thought of in a social-ecological framework. This is relevant when considering ecosystem services—the benefits that people derive from ecological processes and properties. As relevant actors move through a connected landscape-scale network, particular services may “flow” better across space and time. For this special issue on dynamic landscape connectivity, we discuss the concept of social-ecological networks using urban landscapes as a focal system to highlight the importance of social-ecological connectivity to understand dynamic urban landscapes, particularly in regards to the provision of urban ecosystem services.

The evidence base for the benefits of urban nature for people and biodiversity is strong. However, cities are diverse and the social and environmental contexts of cities are likely to influence the observed effects of urban nature, and the application of evidence to differing contexts. To explore biases in the evidence base for the effects of urban nature, we text-matched city names in the abstracts and affiliations of 14 786 journal articles, from separate searches for articles on urban biodiversity, the health and wellbeing impacts of urban nature, and on urban ecosystem services. City names were found in 51% of article abstracts and 92% of affiliations. Most large cities were studied many times over, while only a small proportion of small cities were studied once or twice. Almost half the cities studied also had an author with an affiliation from that city. Most studies were from large developed cities, with relatively few studies from Africa and South America in particular. These biases mean the evidence base for the effects of urban nature on people and on biodiversity does not adequately represent the lived experience of the 41% of the world’s urban population who live in small cities, nor the residents of the many rapidly urbanising areas of the developing world. Care should be taken when extrapolating research findings from large global cities to smaller cities and cities in the developing world. Future research should encourage research design focussed on answering research questions rather than city selection by convenience, disentangle the role of city size from measures of urban intensity (such as population density or impervious surface cover), avoid gross urban-rural dualisms, and better contextualise existing research across social and environmental contexts.

Urban agriculture is widely practiced throughout the world. Urban agriculture practitioners have diverse motivations and circumstances, but one problem is ubiquitous across all regions: insect pests. Many urban farmers and gardeners either choose to, or are required to forego, the use of chemical controls for pest outbreaks because of costs, overspray in populated areas, public health, and environmental concerns. An alternative form of pest control is conservation biological control (CBC)—a form of ecological pest management—that can reduce the severity of pest outbreaks and crop damage. Urban farmers relying on CBC often assume that diversification practices similar to those used in rural farms may reduce insect pest populations and increase populations of beneficial insects, yet these management practices may be inappropriate for applications in fragmented urban environments. In this review, we assess urban CBC research and provide a synthesis for urban agriculture practitioners. Our findings indicate that local and landscape factors differentially affect insect pests and beneficial arthropods across the reviewed studies, and we identify several on-farm practices that can be implemented to increase biological control in urban agriculture.

ABSTRACT: This paper aims to examine the issue raised by the consumption of locally produced food in all its various aspects, and in particular, addresses how this practice contributes to local and global sustainability. It analyzes the different definitions of local food, the strategies used, the implications of the distance traveled in the transportation of food to the consumer's table – food miles, the relationships between local food consumption and sustainability, farming practices that reduce carbon emissions, contribution of urban agriculture to local food, local trading of food produced by rural farmers, as well as a number of relationships between the consumption of local food and human nutrition and health, local food protection and the ability to support local food production for humanitarian actions in disaster situations. The promotion of “local food” is a complex problem covering environmental issues, the economy and health. Transportation is not the only factor that determines how efficient it is to consume local food. Often, the technologies used for agricultural production are those most responsible for the degree of sustainability in the production and supply of food to the population. Local production does not always mean lower emissions of greenhouse gases. In general, the consumption of local foods, produced in ways adapted to the local environment using technologies with an ecological basis, is something beneficial and salutary for the environment, economy and society in general.