Introduction

Since the 1960s, rapid economic growth and industrialisation have concentrated populations in urban areas, and the development of new suburban towns has left existing urban areas faced ageing infrastructure, traffic congestion and pollution (Jang et al. 2017;Lee 2016;Park et al. 2016). In Korea, urban renewal projects were implemented to address this rapid urban decline and achieved many successful outcomes. However, this caused conflicts among residents due to their method of complete demolition (Gu 2021), and the meaning of urban regeneration is currently changing around localized maintenance, resident participation, and sustainability (Jung 2018). Thus, it requires an approach in which public institutions and local residents work together to resolve village issues and promote community restoration and revitalization, rather than the traditional public institution-driven method (Fox-Kämper et al. 2018;Jin 2012).

In 1890s of United States, garden construction in urban occurred as community garden, which social phenomenon showed the expansion into the public (Armstrong 2000). Community gardens contribute to the health effect enhancement, social strengthening, and urban biodiversity (Goddard et al 2010;Howorth et al 2020;Kang et al 2020;Lee and Jeong 2020). These changes have highlighted gardens as a link between urban regeneration and resident participation, creating social values, such as food production and community revitalization and-improving urban aesthetics (Egli et al. 2016;Park et al. 2016). Accordingly, gardens established in the cities could make participants to feel a sense of accomplishment (Scott et al. 2020;Tournier and Postal 2014) and to revitalize the local community by improving relationships with neighbors (Lee 2019b;Teig et al. 2009). In addition, traditional gardens in usual have been established by people themselves as places of participation and community recovery through garden tending in the contemporary period (Sim and Zoh 2015). Therefore, the concept of a community garden that can be utilized in the city is defined as a high-quality green space—a space for physical and mental recovery, community solidarity, and creating social and cultural content not only in underdeveloped areas but also in daily living areas.

Although various functions of the garden were dealt with in some previous studies (Park et al. 2017a;Park et al. 2017b;Lee 2005;Tracey et al. 2020);, which comprehensively considered the detailed functions covered above were insufficient and there was also a lack of research that substituted the function of the garden in the actual case. To establish that gardens play various roles in a city, it is necessary to classify their types based on their function. Hence, this study was conducted with field surveys of gardens in the city to categorize the types based on their functions in Korea through interviews with users and stakeholders. The findings of this study might serve as guidelines regarding the establishment, operation, and management of each garden type in the future.

Materials and Methods

First, the functions and effects of gardens identified from previous studies were clustered into similar concepts (Fig. 1). To ensure validity, the garden function types were named after opinions were gathered from expert meetings. Next, field surveys were conducted on 31 cases over four years (2019– 2022) to identify the gardens with addresses, areas, land types, detailed facilities, operating programs, and functions. Finally, field survey data were applied to supplement the above redefined classification criteria and items for the city gardens, and the current status of gardens by type was analyzed.

Keywords Identified for garden functions from literature review

Keywords were searched regarding garden functions, effects, roles, types, and services, and relevant literature was extracted from Korean and international journals, reports, and theses. The key results from the literature on the functions of gardens, in line with the study topic, were summarized and organized by keywords (Table 1). The detailed functions of gardens were represented by consolidating similar terms when there were overlapping meanings due to similar words. The detailed functions of the listed gardens were classified and clustered into related concepts.

An analysis of Korean and international literatures about the functions of gardens showed that gardens in modern cities communicate with local residents and contribute to the recovery of community life (Lee and Jeong 2020;Park et al. 2017a). With the productive directly growing eating crops (Egli et al. 2016;Guitart et al. 2014;Martin et al. 2017), gardens have been found to improve landscapes by providing natural beauty to the city (Gil and Park 2022;Kim 2021;Park et al. 2020) and to increase the value of - ecological network and biodiversity in city (Goddard et al. 2010;Sierra-Guerrero and Amarillo-Suárez 2017;Speak et al. 2015). Gardens also provide psychological peace through contact with nature (Kang et al. 2020;Lee 2019a;Nordh and Østby 2013) and help maintain physical health through growing plants (Egli et al. 2016;van den Berg et al. 2010). Furthermore, gardens increase the value of buildings (Lee 2005) and serve as a place for environmental education (Mo 2021;Lee 2005). 5 functional types of gardens have been classified through the previous studies, these are social, cultural, environmental, economic and health benefits (Table 1).

Focus group interview (FGI) with Identified keywords about the functions

An expert questionnaire survey was conducted to validate the types of identified functions. The interviewees included 12 experts with garden-related work experience more than 10 years and a Doctor of Philosophy (Table 2). As data for the FGIs, a questionnaire was distributed, including questions about selecting the function types of gardens and representing the degree of agreement between the functions on a 4-point Likert scale. Additional questions were asked during interviews. Face-to-face and online meetings were conducted from October 12 to 13, 2022. The final decision on the garden types was made based on the questionnaire results and the FGI participants’ opinions. As a result of the FGIs, 4 types of gardens were classified: socio-cultural, environmental, economic, health, as social and cultural were combined into socio-cultural.

Classify the functions of community gardens by case (study location classification)

To validate whether garden types could be applied to gardens in cities across Korea, community gardens surveyed from 2019 to 2022 were classified into 4 types. The scope of this study included 31 locations of gardens established in urban regeneration and environmental improvement projects in Korea, including four from the Community Garden Establishment Resident-Suggested Project (Seoul), 20 from the Citizen Participatory Village Gardening Project (Gyeonggi-do), six from the Village Garden Project (Ministry of Security and Public Administration), and one from the Green Fund Support Project (Korea Forest Service). The purpose, shape, and characteristics of gardens were identified from a survey of their current status and interviews with stakeholders, and the most suitable types of urban gardens were selected.

Results and Discussion

Keywords identified for the concepts and functions of urban gardens

This study was based on the classification of garden functions by Park et al. (2017b) into cultural, environmental, social, and additional functions in economic and healthy in 5 functions (Howorth et al. 2020;Jeong et al. 2017;Kang et al. 2020;Lee 2005;Thompson 2018;Tournier and Postal 2014;Tracey et al. 2020;Scott et al. 2020).

Research trends in social functions (26.5%) focus on their contribution to enhancing local attachment, such as social cohesion and sense of place. The cultural function (12.2%) is focused on educating and engaging. In particular, social connectedness and political and educational effects received the highest proportion of studies. For health functions, psychological assessments (18.4%) predominate, while physiological assessments (6.1%) are less common. For environmental functions, the majority of studies focused on connectivity and regulation (14.3%). It can also be seen that the promotion of urban biodiversity through gardens (6.1%) continues to be studied. As for the economic function, research was mainly carried out on the reduction of social costs (8.2%). The overall proportion of literature shows that the economic function (8.2%) is somewhat under-researched compared to the other functions, suggesting that future research should focus on the economic function of gardens (Table 1). Consequently, the detailed functions mentioned in each previous studies are shown in Table 3.

Types of garden functions classified by FGI

The experts were asked to select five keywords associated with each of the 5 types of gardens classified in the literature that they considered important. Table 4 provides the functions and effects of the types of gardens identified in the expert questionnaire. The social type of gardens showed a strong attachment to the community, improved aesthetics, community revitalization, opportunities for recreation and leisure activities, and improved welfare for local residents. The high importance of items related to community cohesion and urban beautification was similar to previous studies (Egli et al. 2016;Park 2017;Park et al. 2017a), with the exception that crime reduction, education, and experience through gardening were excluded due to the low importance of expert opinion. Other community related items (social bonding, friendship, socialising and interaction) were grouped together as community activation. The cultural type of gardens showed a high level of urban vitality, aesthetics, and connection with nature. This is similar to the results of previous studies (Park 2015;Park et al. 2017b) in that gardens are used to appreciate natural landscapes and pursue aesthetic values, but cultural heritage implications were excluded due to the low importance of expert opinion. The environmental type of gardens showed a high level of resting space for citizens, biodiversity recovery, improved streetscape, linkage with urban green spaces, and an improved urban regeneration environment. Among the ecosystem services of gardens classified in previous studies (Mo 2021;Park et al. 2017b), regulating services such as carbon dioxide reduction and heat island phenomenon mitigation were found to be of low importance in expert opinions. On the other hand, the function as a connecting green space highlighted by Goddard et al. (2010) was found to be important. The economic type of gardens indicated a high level of local welfare, tourism, increased real estate value, eco-tourism and eco-healing, job creation, and local economic revitalization. In Park et al. (2017b), tourism and employment were classified as social functions, but in expert opinions they were classified as economic functions, similar to the classification in Park (2017). The health type of gardens showed a high level of relaxation and healing, improved quality of life, stress relief, stability, and relaxation. This is similar to previous studies that emphasised mental and physical effects (Haworth et al. 2020;Thompson 2018;Schram-Bijkerk et al. 2018;), while achievement and self-esteem, highlighted in Tournier and Postal (2014) and Scott et al. (2020), were excluded due to the low importance of expert opinion.

As the FGI relies on the subjective judgement of experts, we use the inter-rater agreement to calculate the content validity index, which measures how well an item represents the content. According to Lawshe (1975), it is considered valid if the validity index is 0.56 or higher in the content validity ratio (CVR) from 12 experts. For each of the five functions - social, environmental, economic, cultural and health - respondents were asked to indicate how important they thought the corresponding sub-function was for each function in Table 5. The social type of gardens showed a high level of validity in social bonding, local community revitalization, and improved quality of life of local residents, whereas the cultural type showed a high level of validity in the order of natural landscapes, opportunities for recreation and leisure activities, and aesthetics. The environmental type of gardens showed a high level of validity regarding resting space, urban green space connection, and biodiversity recovery. The economic type of gardens showed a high level of validity in ecotourism, eco-healing, sustainable development, and job creation, while the health type showed the highest level of validity in physical activity (Table 5).

During the FGIs, most experts suggested the following opinions regarding the overlap between social and cultural functions:

It is a structure in which detailed social and cultural functions overlap when gardens are classified into five functions. Since cultural functions can be regarded as part of social functions, they should be clustered into a single concept.

“When a society lasts, it develops into a culture. The society referred to in this study is the concept of socialization, and it becomes a culture when socialization is over. Since it becomes a culture only when it is socialized, the focus should be on the social functions of gardens in the early stage. As socialization proceeds by revitalizing the community, restoring relationships within the organization, and generating a sense of understanding and respect for others through effects, such as softness and relaxation provided from parks, and then develops into a culture, it should be integrated into socio-cultural functions.”

“The garden functions showing the public interest would be properly explained only when social and cultural functions are consolidated.”

In addition to expert opinion, previous studies by Pyo and Choi (2021) and Hong and Lee (2021) also have grouped social and cultural together and explained gardens under socio-cultural functions. As a result, four types of gardens were selected: socio-cultural, environmental, economic, and health. Based on the FGI results, the socio-cultural type of gardens included some functions such as attachment to the local community, local community revitalization, urban revitalization, and improved appearances and aesthetics, while the environmental type included resting space for citizens, improved streetscape, improved urban regeneration environment, linkage with urban green spaces, and biodiversity recovery. The economic type of gardens included local welfare, local economy revitalization, tourism, job creation, and increased real estate value, while the health type included relaxation and healing, a sense of stability, stress relief, and improved quality of life (Table 6).

Analysis of types in community garden cases in Korea

The garden cases were classified into four function types based on expert questionnaire survey results. Unlike location and form, much subjectivity is involved in functions during the classification process. Hence, instead of classifying all the functions performed in gardens, this study restricted the classification to the functions found in small-scale gardens established as part of urban regeneration projects and identifiable through one-time field surveys and interviews.

An analysis of the current status showed that the socio-cultural type of gardens included garden-related education, improved landscape, events (community revitalization), and rest (shelter); the environmental type included linkage with green spaces, biodiversity preservation, climate change response; the economic type included linkage with local commercial areas, production activities, profit creation from tourism, and job creation; and the health type included linkage with health and welfare facilities, space for resting and healing, and garden experience activities (Table 7). Most of the 31 gardens studied in Korea were found to have cultural functions. This seems to reflect that this study surveyed gardens where communities such as resident associations and cooperatives participated in establishing the gardens. It was found that gardens included socio-cultural and other functions as characteristics. Based on these findings, the types of gardens were divided according to each case location’s geographical characteristics and functional elements.

In most cases of the socio-cultural type of gardens, there were garden centers, garden docents, and experience and commentary programs, and they were found to be spaces where garden activities were conducted actively as residents led operations and management. It was found that most case locations of the socio-cultural type of gardens considered gardens as revitalizing the local community and improving aesthetics. In the case of Mirinae Village, Bucheon, a garden was created to expand a space for communication between residents, and various types of benches, swing chairs, and sitting walls were thus installed. A garden-based festival was held to promote solidarity among residents, and garden commentary and garden maintenance activities where residents participated in person were also conducted (Table 8).

In the case of Maeholdure, Osan, representing the environmental type of gardens, a garden was established under the mountain, and a school and houses were located nearby, connecting the large green area and daily living space. It was found that gardens were seen as addressing accumulating garbage in the area. The resting space was created with benches and pergolas, rainwater recycling tanks, solar garden lights, and garden facilities that considered environmental factors with recycled materials (Table 8). This study found only three cases of environmental-type gardens with a large green area near mountains that served to respond to climate change or preserve biodiversity, suggesting a lack of environment-type gardens in Korea. Facilities related to climate change response were found to be fragmented facilities, such as rainwater storage facilities or solar gardens, and there was only one case that built a habitat for biodiversity. Given that the built-up area in Seoul is 61.39% (Seoul Open Data Plaza 2019), there are limited, sufficiently large areas for gardens to be established in Korean cities. Options to preserve urban biodiversity include not only parks, but also small-scale gardens, which may serve as a habitat and a connected green space to form an ecological network (Goddard et al. 2010), Urban green spaces with a higher level of biodiversity provide greater physical and psychological benefits to citizens (Fisher et al. 2022;Fuller et al. 2007;Loram et al. 2011). Therefore, it is necessary to actively promote the establishment of gardens that include ecological functions and prepare an ultimate solution to environmental problems.

Six economic types of gardens were found to generate profits through festivals, instructors, and farming association activities or to create jobs for older adults managing gardens. Furthermore, for-profit garden programs, such as horticultural activities, crafts, accommodations, and dining, were also conducted. Sema Art, Osan was found to consider a garden, as workshops were not very active, although there were many of them nearby. An outdoor stage was installed in the garden to hold a village festival with nearby workshops, which was found to have gradually revitalized the local commercial area (Table 8).

The health type of gardens was limited to gardens in medical institutions or welfare facilities, and this study found only one, which was the lowest number among the results. The community garden at Chuncheon National Hospital is characterized by its design that considers patients in the hospital in terms of the garden configuration. Even though they were temporary, garden-based activities were also conducted for patient healing (Table 8). As garden activities help to improve mental health, rehabilitate by increasing physical activity, and assist in coping with long-term diseases (Scott et al. 2020;Thompson 2018;Howorth et al. 2020), it is necessary to consider continuing a program instead of a temporary activity program after establishing a garden. It is necessary to promote the establishment of gardens tailored to the underprivileged, such as older adults, the disabled, and the mentally ill.

Conclusion

This study evaluated various functions of urban gardens based on previous studies and identified and validated function types of gardens through FGIs. 4 Functions were classified based on the actual cases of gardens established in Korea. The socio-cultural type of gardens (75.0%) is a garden adjacent to the daily living space, allowing residents to directly participate in the maintenance and is useful to spread garden activities, thereby revitalizing the local community and improving landscapes. The environmental type of gardens (7.5%) is a garden located around a large green area that connects with other green areas within the daily living area and positively affects residents’ resting spaces and biodiversity. The economic type of gardens (15.0%) is a garden that coexists with the surrounding commercial area to attract visitors and boost the local economy. The health type of gardens (2.5%) can be defined as a garden that enhances quality of life by providing a gardening and healing program designed to improve the health of its intended participants. The analysis of cases in Korea showed that there are many socio-cultural type gardens, while there is a lack of gardens of the other types - resulting from the characteristics of the housing culture in Korea, where apartments account for most houses, and consequently, the socio-cultural type of gardens also seems to account for the majority. The results of this study may serve as a reference for determining the functions to be pursued when establishing a city garden. Furthermore, it is necessary to prepare guidelines to introduce different types of gardens, as well as the socio-cultural type of gardens.