Relationships between urban human–food connection dimensions
This study has examined different types of internal and external HFC of urban vegetable gardeners and how HFC is related to PEFB. Four different types of HFC were distinguished: food harvesting and experiential food interaction as forms of external HFC, and food discovery and food consciousness as internal expressions of HFC. This suggests that practices of active urban gardening encompass various dimensions of HFC. The fact that various HNC dimensions do not operate in isolation but are related to one another (sensu Ives et al. 2018), was supported by correlations among the extracted HFC dimensions (see Table 4). This supports conclusions by Tam (2013) and Whitburn et al. (2019) that measuring HNC by multidimensional scales such as cognitive and affective ones is important for understanding and determining interventions promoting greater PEB. Interestingly, when comparing the four extracted HFC dimensions, the correlations suggest that in particular food harvesting as a ‘body-oriented’ HFC has the strongest and positive correlation with food interactions as another physical HFC. Food consciousness as a ‘mind-oriented’ HFC is significantly and positively correlated with food discovery as another cognitive dimension of HFC. While there appears to be a distinction between external ‘body-oriented’ and internal ‘mind-oriented’ food connections, all four HFC dimensions have significant positive relationships with each other. The weakest relationship can be found for food harvesting and food discovery (r = 0.18, p < 0.01); the strongest relationship was between food interaction and food discovery (r = 0.42, p < 0.01). Thus, food interaction might be considered as an intermediary or ‘translating’ form of nature connection that links body-oriented and mind-oriented HFC.
However, the correlations do not necessarily infer causal relationships, and it is likely that bi-directional interactions exist among HFC dimensions. Indeed, this interconnected, multi-relational ontology is central to a systems perspective on human–ecological phenomena (Folke et al. 2016). For instance, the positive relationship between urban gardeners’ attitudes towards food and frequency of experiential garden use can be supported by findings of Lin et al. (2014). They found that in particular nature orientation is a strong determinant of visiting urban parks compared to green space accessibility (Lin et al. 2014). However, the frequent use of the vegetable gardens for experiential food interactions can also be a consequence of more mind-based HFC such as positive attitudes towards self-grown food. Further, results from a study by Soga et al. (2019, p. 357) suggest “(…) that people with a stronger inclination towards nature sought out more experiences with wild flowering plants.” Future research is needed to understand how various dimensions of HFC influence each other.
Relationships between urban gardeners’ characteristics and urban human–food connection
Bivariate correlations with sociodemographic data show positive but weak significant correlations between the length of patch rental and food consciousness (r = 0.15, p < 0.05) and food harvesting (r = 0.20, p < 0.01). These findings can be discussed through the lens of sense of place as embodied experience (West et al. 2020), describing relationships between individuals and their specific environments (e.g. Giuliani and Feldman 1993; Raymond et al. 2010). Place attachment is discussed as an important factor for strengthening HNC (Ives et al. 2017; Klaniecki et al. 2018) and environmental stewardship (Gottwald and Stedman 2020). Related studies suggest that place attachment evolves over time and depends among other things on the length of residence (Jorgensen and Stedman 2006). Also, the time spent in nature positively influences emotional affinity towards nature (Kals et al. 1999). Our findings show that the frequency of using vegetable gardens is significantly and positively associated with body-related HFC, in particular experiential food interaction (r = 0.55, p < 0.1) and food harvesting (r = 0.25, p < 0.1). This is perhaps to be expected given the conceptual similarity of the concepts. However, the relationship does support the potential for a pathway for reconnecting people to nature, whereby frequent interaction with nature can foster lifestyles and diverse practices based on nature (Ives et al. 2018).
Some differences were observed between results from this study and findings by Artmann et al. (2020). Internal and external HFC appeared strong in our case, with data depicting frequent resident engagement with urban food production. Conversely, Artmann et al. (2020) reported that edible areas providing free food on public spaces were rarely used (see “the introduction”). The present study showed that vegetable gardeners harvest more vegetables and thereby use the garden more often for physical exercise and learn more about food and diet through active gardening compared to residents of the edible city (Artmann et al. 2020). Since the two studies used different case studies and methodological approaches (e.g. comparison of a selected focus group in Munich vs. the whole population in the edible city Andernach), any conclusions that active urban gardening is more efficient for promoting HFC than implementing urban gardens in a city with lacking civic participation, is not conclusive. Thus, further in-depth investigations under similar study conditions are needed.
Correlation between the HFC dimensions, gender and education show only small effect sizes. Between age and HFC no relationships were found at all supporting the findings by Cleary et al. (2018) that HNC interventions are important for older and younger people. Gender differences in HFC were small but significant, with women having stronger HFC regarding food consciousness (r = 0.15, p < 0.05), experiential food interaction (r = 0.14, p < 0.05) and food harvesting (r = 0.15, p < 0.05). In fact, women identify in another case study as lifestyle gardeners prioritizing plant diversity, experiential activities and communing with the nature in the garden (Taylor et al. 2017). These indications pave the way to connect the HNC debate with the partnership with nature discourse and its linkages with feminism (Knippenberg et al. 2018) suggesting that women are closer to nature than men (Roach 1991). This may also explain why more women (74%) than men participated in the survey (25%) suggesting that more women are gardening than men, such as also found in another German-wide study (Winkler et al. 2019). Some previous studies reflecting the role of gender in urban food production found that drivers for engaging in urban agriculture do not differ between men and women but that female gardeners in particular see themselves benefiting of stress relief compared to men (Robertson 2013). Taking into account that urban conditions such as noisy and crowded environments can be considered as being in particular stressful (Hartig and Kahn 2016), health benefits perceived by female gardeners might be one explanation for why women particularly engaged in urban vegetable gardens in a big city such as Munich. In terms of any relationship between psychological well-being and PEB, Whitburn et al. (2018) assumed that urban HNC can strengthen mental benefits, which might translate into PEB, or in our case internal food consciousness. Further research analysing drivers of female urban food producers are the need of women to secure supplementary source of food in Cameroon (Ngome and Foeken 2012) or to overcome any racial and class-based barriers such as by black women activists in Detroit, US (White 2011). Since both issues where not relevant for this case study, it needs future research analysing why women are participating in urban gardening in Central Europe compared to men.
The weak but significant negative correlation between food discovery and education may indicate that residents with lower levels of formal education benefit more greatly from urban gardens. A similar result was shown in a case study in Barcelona, Spain (Camps-Calvet et al. 2016). In fact, evaluating HNC is a crucial variable to assess the effectiveness of environmental education programs (Frantz and Mayer 2014).
The role of food consciousness
The regression analysis showed that food consciousness was the only HFC dimension significantly related to PEFB. Further, only the HFC dimension was statistically correlated with all the other dimensions (harvesting, interaction and discovery) (see “the relationships between urban human–food connection dimensions”). These findings provide evidence for both the conceptual and empirical distinction between HFC dimensions, and their inherent relatedness. Closer examination of the items that comprise this dimension revealed possible explanations for why only food consciousness was related to PEFB. The items that loaded on this factor represent life attitudes, awareness and concerns related with food consumption without linking directly to the specific vegetable garden. Thus, the dimension can be considered as representing ‘indirect’ nature connections (Soga and Gaston 2020), possibly related to notions of environmental identity (Clayton 2003). In fact, the strength measured between HNC and PEB can be influenced by taking into account items that indirectly measure PEB, such as environmental identity (Hatty et al. 2020; Whitburn et al. 2019). Thus, a comprehensive meta-analysis of scientific studies assessing relationship between HNC and PEB by Whitburn et al. (2019) showed that scales using such items correlate more strongly with PEB than scales without including such items.
In contrast to food consciousness representing ‘indirect’ nature connections and mediating PEFB, the three HFC dimensions food harvesting, food interaction and food discovery can be considered a more immediate human–nature interaction explicitly referring to the vegetable gardens. The negative relationships found between food harvesting and PEFB, and between frequency of patch use and PEFB (albeit nonsignificant), may be explained by urban gardeners who harvest more and use the garden more frequently, requiring less purchased food. In this regard, analysing different HFC dimensions and their impact on PEFB need to be context-specific, taking into account the close interplay between direct HFC via food harvesting and indirect HFC as sustainable food consumption. Thus, food self-provisioning can be considered a PEFB in terms of a positive future-oriented and transformation-enabling everyday practice “(…) by subjects who consciously reflect on and challenge the food system’s deleterious social and environmental effects.” (Jehlička et al. 2019, p. 513). This sentiment was expressed by an urban resident who commented in the end of the survey: s/he supported the urban vegetable garden project as a way of strengthening ecological agriculture and environmental education, considering this to be an activity that was simultaneously meaningful and enjoyable.
This statement together with the crucial role of food consciousness fostering PEFB can also be reflected under the well-known slogan "think globally, act locally". In this regard, our findings suggest that immediate HFC (namely local urban gardening and its producing immediate urban garden-body- and mind-related HFC-dimensions) is related to a broader sphere of HFC (characterising interconnections between local action and wider global environmental impacts displayed by food consciousness) that in turn is translated into PEFB. Thus, food consciousness and its related items mainly reflect concerns of food consumption and environmental impacts as well as food as part of life attitude. Indeed, other studies found that individuals’ self-perception about pro-environmental concerns are crucial for predicting PEB (Carfora et al. 2017). Lumber et al. (2017, p. 5) suggested that: “(..) the desire to protect nature may not be a result of connectedness solely, but serves as a route to connectedness in its own right”. This calls for more research to capture the full complexity of HNC taking into account positive feelings such as joy in nature and negative emotions when it comes to nature destruction and coping with global and local environmental loss (Chawla 2020).
These findings fit well into the debate on an embodied HNC and its role for fostering earth stewardship. Cooke et al. (2016) emphasised that global sustainability needs local entry points that can be entered by combining acting (here: body-related HFC including food harvesting and food interaction) and thinking (here: mind-related HFC including food discovery and food consciousness) in our everyday surroundings that are in our case study the urban vegetable gardens (see Fig. 3). Therefore, based on our results, we suggest that there is a possible causal pathway from (i) experiential, ‘external’ connections with food landscapes that develop (ii) an ‘internal’ consciousness of the importance of food personally and ecologically, leading to (iii) behaviours that express this consciousness. Exploring this pathway in more depth is an avenue for future research, especially the importance of developing sustainability mindsets in order to bring about behaviour change. For example, nature and sustainability education programs should not only provide mind-based information, but should consist of theory and practice. Ideas from deep ecology can provide effective practical exercises to foster awareness of self and nature in the immediate nature such as through nature blessing, sensual nature observation or mimicking animals (Kowalewski 2002). In terms of urban planning and development our study supports the call by Colding et al. (2020, p. 7): “Planners and urban designers need to foster arenas in cities that promote collective action and where urban residents can interact with nature more fundamentally with their heads, hands and heart.“
In this regard, interventions for fostering strong urban HNC and PEB should not only take into account vegetable gardens and their active gardeners. In general, urban residents are considered to lack nature experience harming the appreciation of the natural world (Soga and Gaston 2016). According to Klyen et al. (2020), urban residents connect in terms of their knowledge, emotions or behaviours with various formal and informal urban green spaces and its elements, such as with river corridors, home gardens or trees. For children, private gardens are most preferred spaces to connect with nature (Hand et al. 2017). In this regard, urban gardening projects such as in Munich can be considered crucial activities for compensating in cities often lacking private gardens. Statements from survey participants found in the open comment field in the end of the questionnaire support this assumption. For instance, one participant emphasised that her/his child loves to join the vegetable garden for harvesting since lacking a private garden for similar nature experiences. Another gardener expressed a desire for their own garden, which cannot be realised due to high rental prices, but was compensated through renting a vegetable garden. Beyond the need to compensate for a lack of private green spaces, urban gardening projects can be a valuable entry point to attract various kinds of urban residents, who might be interested in learning about or contributing to urban gardening techniques, socializing, healthy food or nature protection. Thus, urban food production has sufficient upscaling potential as a mean for fostering HFC and sustainability transformation (Sartison and Artmann 2020).
Study limits and future research
Limitations were related to our study methodology. First, by conducting an online survey spread by contact persons, urban gardeners without email contact or not involved in the mailing list, might not have been reached. However, to reduce this risk the survey was additionally promoted during a kick-off meeting for the gardening season in March 2019. Secondly, to capture PEFB the results are based on self-reported estimates on actual behaviour. Future research could further validate this by using assessment methods such as diaries used for analysing patterns of food consumption through a time series (Cheng et al. 2007).
Thirdly, the study focuses on urban vegetable gardens, therefore we do not claim that the findings can be transferred to all types of urban food production. Recent research suggests that various types of urban gardens, such as community, allotment or oyster gardens support environmental stewardship (Andersson et al. 2014; Krasny et al. 2014; Langemeyer et al. 2018). However, if there are any difference between types of urban gardens and their impact on various HNC dimensions and PEB needs further in-depth research whereby our framework can function as an analytical framework.
Since food consciousness as mind-based HFC is in our study a key predictor for PEFB, we suggest that future research should further elaborate on how to assess and record internal HNC. In general, to deepen the understanding of PEB, recent research claims that sustainability science needs to put more weight on the neglected inner lives of individuals as a means to sustainability transformation (Ives et al. 2020). Since our variable explaining food consciousness provides only weak correlations with PEFB, future research should consider related psychological concepts such as biocentric or ecocentric values (Dietz et al. 2005), and exploring urban gardening and consumer behaviours from a social practice perspective (Strengers and Maller 2015). Besides input for theory-action education programs, ideas related to deep ecology and its associated concept of the ecological self, emphasizing that all human and nonhuman objects are interconnected in a vast web of relationships (Bragg 1996; Naess 1973), can provide insights on how to further elaborate on internal HNC in the context of transforming human behaviour towards sustainability. Moreover, to foster creativity and inter- and transdisciplinary sustainability research that can be constrained by often abstract scientific language (see also Ives et al. 2020), we suggest that future urban HNC research should explore more greatly the “inner human nature” by linking the research subject (urban residents and their inner world such as mental well-being, personal values and worldviews) and object (external nonhuman nature such as urban gardens).