Positive aging benefits of home and community gardening activities: Older adults report enhanced self-esteem, productive endeavours, social engagement and exercise (2024)

Positive aging

Despite varying definitions, successful or positive aging is generally accepted to entail more than an absence of disease and the preservation of physical and cognitive functioning.³ Most models of successful aging identify the importance of activity^3–5 and include continued and active engagement in social and productive life activities.⁵ Older adults possess enormous reserves of capacity in terms of functioning, and aging is merely another stage in development according to Selection, Optimization and Compensation theory.⁶ As such, successful aging is a dynamic between losses and gains, that is, compensating for losses or limitations in functioning with gains in the development of new skills or tangible support (e.g. social or technological) where necessary. Positive aging is a psychological mind-set that reflects an individual’s ability to cultivate well-being though later life, despite declining functioning; having a positive attitude to aging is a form of psychological resistance to age-related declines.⁷ According to these successful aging theories, activity engagement despite age-related decline in physical functioning increases later-life well-being. Attending to the daily task of gardening may provide an outlet for purposeful activity, which is associated with increased self-esteem, creativity and mental stimulation.⁸ While gardening is a productive and gratifying activity for many, the well-being benefits of gardens may be more rudimentary and linked to a basic love of nature and the restorative properties of natural environments. Maintaining some form of engagement in leisure gardening, especially as one ages, may be crucial to the older adult gardener’s continued well-being and is therefore an important topic to explore in research.

Psychological benefits of gardening

Exposure to nature through gardens and gardening activities can enhance psychological well-being through emotion regulation and relief from stress. Classic early research shows that viewing nature through windows or in pictures can positively affect stress recovery, lowering blood pressure and slowing heart rate.^9,10 Because natural environments require less effortful attention and may act as a distraction from daily hassles,⁹ in particular for frail older adults, simply being in a garden or viewing elements of a garden may provide benefits such as relaxation and restoration.

Gardens offer older people a place to reminisce about the past. Bhatti et al.¹¹ examined the autobiographical discourses of everyday people who responded to a social research directive to write about the ‘importance of their gardens’. ‘Being’ in the garden evoked memories of childhood gardens, real or imagined. Touching a particular plant or smelling a certain flower may transport a person back to their childhood.¹¹ Therefore, memories of past gardens, which can be invoked through touch or smell in the present in a garden, may serve to cultivate feelings of well-being for older adults. This is in line with the ‘nostalgia’ literature that supports that these reflections on the past imbue life with meaning and self-continuity, bridging the past to present¹² through the recreation of experiences and relational bonds.

Gardening provided older adults with opportunities for nature connection,¹³ nurturing the environment and the responsibility of caring for and raising plants,¹⁴ and for being creative in planning, designing and choosing suitable plants for a garden.¹⁵ When older adult gardeners are driven to learn about new plants or plan new gardening projects, it is an opportunity for mental stimulation as well. Opportunities for cognitive enhancement exist if they belong to gardening societies or groups where the focus is often on learning about new plants, a history of gardening, or learning the Latin names of plants, for example.

Physical benefits of gardening

Gardening requires regular and continuous care; therefore, for older adults actively engaged with their home gardens, gardening provides opportunities for increased physical activity, which can prevent osteoporosis, reduce the risk of some cancers, Type 2 diabetes, depression and heart disease.¹⁶ These are significant contributors to health care costs and pose a risk to older adults.¹⁷ One UK study found that moderate to heavy gardening activity of four or more hours per week was associated with significantly reduced risk of morbidity and mortality rates in a sample of middle-aged and older men with cardiovascular disease.¹⁸

Social benefits of gardening: community gardens and gardening clubs

Benefits may accrue for individuals that belong to a gardening group. Gardening groups offer a way for people to connect with nature and each other, allowing social benefits to accrue. Group membership may be especially important for older adults, especially during periods of change such as retirement from paid employment.¹⁹ Connecting with other members of a gardening group allows people to receive social support and to contribute positively to the lives of others, an important protective factor against isolation and loneliness.¹⁹

In Australia, gardening groups are non-profit organizations where members may meet on a regular basis to attend group discussions or educational seminars, or to maintain and cultivate fruit, vegetable, herb and ornamental plants in small public allotments.²⁰ Group participation in gardening activities can build social capital and enhance group cohesiveness and community well-being by providing a physical location to meet other people with shared interests and common goals.^21–25 Gardening group membership can provide opportunities for an increased sense of achievement and pride through collaborative endeavours towards environmental restoration²⁵ and cultivating and sharing herbs, fruits and vegetables.²⁰

Positive aging and gardening

These studies have demonstrated that gardening as a leisure pursuit may maintain or promote an older adult’s psychosocial and physical functioning and therefore enhance their quality of life. Despite age-related limitations in physical functioning, gardening participation may provide important occupation and activity engagement. Membership in communal gardening groups offers a context for social interaction and collaboration, which may be particularly important for socially isolated older adults. Older adults have considerable leisure hours available, and gardening is a popular leisure activity for them, yet it remains one of the least systematically studied.²⁶

Study aim

We aimed to systematically examine the positive aging benefits of leisure gardening for community-dwelling older adult gardeners. Specifically, we examined relationships between gardening characteristics, involvement, and gardening benefits. In addition, we compared the results for members of gardening groups with non-members.

Participants and procedure

Participants were recruited through invitation via gardening clubs, seniors’ groups, research databases and by word-of-mouth. A minimum of 176 participants were targeted, based on G*Power analysis. The survey was distributed via online or hard copy. Informed consent was implied by returning the survey form (hard copy versions) or by agreement and moving forward with the survey (online). Participation was voluntary, no incentive was provided. Eligible participants were self-identified older gardeners aged 60 years and over who lived in the community and gardened in their own homes or community gardening groups for a minimum of 1 h/week.

A self-administered gardening survey was constructed consisting of quantitative and qualitative data: (a) demographic information questions; (b) several open questions about involvement in, and feelings about gardens; (c) activity inventory;²⁷ (d) attitude statements (‘gardening benefits questionnaire’); (e) self-rated health and quality of life; and (f) Attitudes to Ageing Questionnaire (AAQ).²⁸ The qualitative data, that is, open responses, were extensive and are reported elsewhere.²⁹ The survey was first pilot tested with a small sample of older adult gardeners (N = 40) and subsequently refined to improve face validity and content validity. The final version of the survey was delivered online, or via mail together with a reply-paid envelope, to potential participants across Australia. This resulted in the return of 362 surveys: 129 via the online survey site and 202 via mail. Thirty-one surveys were excluded because the respondents did not meet the selection criteria of gardening for more than 1 h/week; 331 were retained for analyses.

For the purposes of this study, gardening was defined as any activity that involved tending (planning, planting, watering, nurturing) outdoor ornamental plants, shrubs or fruit plants in a garden, or in pots or containers, including passive engagement such as wandering through gardens, relaxing in or viewing gardens, and active engagement, such as cultivating plants, mowing lawns, weeding and raking.

Materials and instruments

Characteristics of sample

Table 1 describes the demographic characteristics of the sample. Participants ranged in age from 60 to 95 years (M = 68.90, standard deviation (SD) = 7.36). Most participants resided in a house (90.60%) in an urban area (77.80%); length of residency varied between 1 and 69.08 years (interquartile range = 5.50–25.20 years). On average, participants engaged in gardening activities for 1–40 h/week (M = 10.40, SD = 8.17). Most participants had been gardening for several years (Table 1), and a majority (60.90%) wanted to spend more time gardening than they currently were (M = 16.91 h/week). Furthermore, most participants reported their garden was an average house block (up to one-quarter acre), with 22.40% being greater than this and 21.80% smaller than this; 17.80% of gardens were mostly raised planter beds, courtyard or balcony gardens; 4.00% were mostly potted plants. A range of gardening activities²⁹ and the percentages of respondents who participated in them are shown in Table 2.

Perceived health was measured using 5-point Likert-type scales, with response options ranging from ‘poor’ to ‘excellent’, with higher values indicating better health. As shown in Table 1, the majority of participants rated their health as ‘good’ to ‘excellent’, and a majority (69.20%) rated their health was ‘about the same’ compared with 1 year ago. There was a significant negative correlation between age and self-rated health, r = .20, p ⩽ .001. On average, participants’ self-rated health scores decreased as age increased. Participants’ gardening group membership was measured by a dichotomous variable (yes/no). Approximately half of the sample (52%) reported they belonged to a gardening club or group.

Data reduction of gardening benefits items

PCA determined the factor structure of the full gardening benefits dataset. Inspection of the component correlation matrix and relationships between factors confirmed the suitability of varimax rotation. The Kaiser–Meyer–Olkin (KMO) measure verified the sampling adequacy for the analysis, KMO = .91 and all KMO values for individual items were well above the acceptable limit of .5 (Field, 2009). Bartlett’s test of sphericity χ²(861) = 6799.59, p = .000, indicated that correlations between items were sufficiently large for PCA. We initially obtained eigenvalues for each component in the data. Eight components had eigenvalues over Kaiser’s criterion of 1; in combination, they explained 63.45% of the variance. Table 3 shows the factor loadings after rotation.

AAQ

Factor analysis of the AAQ showed support for the proposed three-factor model of the scale,²⁸ with all items loading on the appropriate factors: Psychosocial Loss, Physical Change and Psychological Growth. The factor scales showed good internal consistency, in line with earlier validation studies of the AAQ (Laidlaw et al., 2007); scale reliability and scale means are shown in Table 3. The total scale means indicated that on average this sample were likely to endorse positive attitudes to aging, expressed through responses to the items on the Psychological Growth (M = 28.17; ‘It is a privilege to grow old’) and Physical Change subscales (M = 27.73; ‘It is important to take exercise at any age’) subscales. Furthermore, they were less likely to endorse a negative attitude to aging as demonstrated by responses to the items comprising Psychosocial Loss subscale (M = 15.22; ‘Old age is a depressing time of life’).

Correlations among AAQ subscales, gardening benefits scales and demographic variables

Preliminary correlation analyses were performed at α = .05 to explore potential relationships between the variables of interest. As shown in Table 4, these yielded significant zero-order correlations between self-rated health and age and between self-rated health, time spent gardening and size of garden. Significant correlations were observed among the gardening benefits scales and the AAQ scales as shown in Table 4.

There was a significant positive correlation between age and the AAQ Psychosocial Loss subscale (all ps < .05) indicating that increasing age was related to increasing endorsem*nt of the negative attitude of old age being characterized as a time of psychosocial loss for participants. However, there was no significant relationship between age and Physical Change, or age and Psychological Growth; attitudes towards physical change and psychological growth were unrelated to age for this sample of older gardeners.

Self-rated health was significantly positively correlated with Physical Change; as self-rated health increased, endorsem*nt of positive aging experiences and functioning healthily also increased (all ps < .05). Positive attitudes to taking exercise at any age, keeping fit and active as one ages, as measured in the scores on this scale, were associated with participants’ increased self-rated health. Self-rated health was not statistically related to the Psychological Growth subscale; participants were no more or less likely to endorse the positive attitude that old age was a time of development and wisdom based on their self-rated physical health. Thus, it appeared that self-rated health played an important role in participants’ negative psychosocial and physical attitudes to aging, but not in positive psychological attitudes.

Time spent gardening was significantly positively correlated with several of the gardening benefits scales, including Restoration, Attachment, Physical, Social, Identity and Purpose (see Table 4). The more time spent gardening, the more benefits that accrued. However, time spent gardening was not correlated significantly with any of the AAQ attitudes to aging subscales, Psychological Growth, Physical Change and Psychosocial Loss (as shown in Table 4).

Time spent gardening was neither significantly correlated with age nor self-rated health, indicating that age and health status did not have an effect on the amount of time that participants engaged in gardening activities. However, self-rated health was significantly positively associated with ‘size of garden’; that is, increases in ‘size of garden’ were related to increases in (positive) scores of self-rated health. These results seem to suggest that older adults’ gardening areas may change as they age or as their health changes, although the amount of time they spend gardening does not change. In other words, they may modify the size of their gardens relative to their age and health status in order to maintain their level of activity.

Members and non-members of gardening groups

A series of independent sample t-tests were conducted to assess any differences in responses between members and non-members of gardening groups. The results of these analyses are shown in Table 5. There were significant differences between members and non-members of gardening groups for several of the gardening benefits (correlations and significance levels are reported in Table 6). According to these results, being a member of a garden club or group augmented the positive benefits of gardening, such as Restoration, Attachment, Physical, Social and Identity benefits.

Standard multiple regression analyses

To test the strength of the relationship between positive attitudes to aging (AAQ scales Psychological Growth and Physical Change) and the benefits of gardening scales (Restoration, Attachment, Physical, Social, Spiritual, Identity, Purpose and Shared), a series of regression analyses were conducted. Psychosocial Loss was not included in the analyses as the only significant zero-order correlation observed with this subscale was with age. Gender was included in the regression only as a control variable as there were so few males compared with females in the sample.

Moderated multiple regression analyses

Study overview

This study explored the perceived psychosocial and physical benefits of leisure gardening for a group of older community-dwelling adults, and the relationship between their motivations to garden and attitudes to aging. In addition, the perceived psychosocial and physical benefits for older adults who participated in gardening groups were compared with those who did not belong to such a group. Overall, the results showed that older adults took part in numerous gardening-related activities and reported that they obtained psychological, social and physical benefits from these; in addition, the more time spent in these activities, the more benefits accrued for participants. There were three main findings. The first was that restoration benefits and physical benefits were the main aspects of gardening that were associated with participants’ positive self-perceptions of their own aging. The second was that being involved in a gardening group led to accrued benefits. The third was that regardless of engagement level, access to the biophilia effects of gardens was key to enhanced well-being.

Defining gardens

The conventional definition of a garden as the green space surrounding an average house block is challenged in this research: Participants’ ‘gardens’ varied greatly in size and function. These might have comprised a balcony with potted plants, or raised planter beds in a courtyard, through to large quarter-acre house blocks. Watering the garden was the most common gardening activity reported by participants. The results of this study suggest that gardening, however defined in terms of size or activity, is a key leisure pursuit for older adults that is fundamental to their well-being. These results provide support for the suggestion that gardening could be an effective and affordable population level intervention to promote or sustain the health and well-being of older adults. Older adults could be encouraged to actively garden as a preventive health measure, or to engage in passive gardening pursuits, for example watering the garden to reduce mental fatigue, as a health promotion measure.

Positive attitudes to aging, self-rated health and gardening

The results indicated that poor self-rated health played an important role in participants’ negative psychosocial and physical attitudes to aging, but it did not have an effect on their positive psychological attitudes to aging. That is, participants may have experienced poor physical health but this did not necessarily determine their psychological attitudes to aging. Furthermore, poor self-rated health did not have an effect on the amount of time that participants spent gardening. In other words, poor physical health did not limit participants’ time spent gardening, nor affect their positive psychological attitudes to aging.

Physical benefits of gardening

Physical benefits obtained from gardening were not unexpectedly the most important predictor of participants’ positive self-perceptions of their aging related to Physical Change. The regular and continuous care of maintaining a garden provides an outlet for meaningful engagement in life’s activities, an important aspect of successful aging.⁵ Furthermore, four or more hours of moderate to heavy intensity gardening activity on four or more occasions per week was related to significantly reduced risk of morbidity and mortality rates in a sample of older participants experiencing cardiovascular disease in a UK sample.¹⁸ This current sample of older participants spent an average of 10 h/week gardening at varying intensity levels, including weeding and raking, watering, tending plants and shrubs, composting and mowing the lawn. Gardening may be one way to offset declines in other physical activities, such as when participation in other recreational or sporting endeavours declines.

Time spent gardening: a dose–response relationship

More time spent engaged in gardening activities led to an increase in the magnitude of the benefits experienced by participants – in particular, Restoration, Physical, Social, Purpose and Identity benefits, therefore suggesting there is a dose–response relationship between time spent gardening and benefits. In other words, the extent to which older adults experience gardening benefits may be affected by the level of time investment in gardening.

Restoration benefits of gardening

Restoration benefits of gardening were significantly associated with positive attitudes to aging, especially Psychological Growth (positive factors about growing older). Exposure to nature through one’s garden can enhance psychological well-being, through emotion regulation and relief from stress. Positive emotional responses such as rejuvenation, peace and recovery from stress that typified biophilia theory³³ underpinned the Restoration subscale (derived from the gardening benefits questionnaire items). Biophilia theory³³ suggests that because humans evolved in verdant environments, we find natural environments more relaxing than artificial ones. Gardens were perceived to be restorative places in prior research;²⁶ the participants of this study also endorsed this attitude. Our participants established daily contact with nature through gardening, finding it especially restorative.

Restorative benefits were not affected by the size or type of garden. The absence of a relationship between size of garden and either of the Restoration or AAQ Psychological Growth subscales suggests that gardening benefits can be obtained regardless of garden size. Access to nature, at least through having potted plants or courtyard gardens and with consideration of garden characteristics³⁴ and vegetation density,³⁵ may be important considerations for older adults downsizing their homes and gardens.

Membership to a garden club

Experiencing the restorative properties of gardening is not only a solitary experience as Ashton-Shaeffer and Constant found, but can also be a shared experience according to the present study. For example, gardening group members report exchanging stories or pictures of gardens and plant cuttings, as well as visiting gardens and community gardening events. Home gardeners who belonged to a gardening club or society experienced additional Restoration, Attachment and Physical benefits resulting from membership. Being a member of a gardening club was also associated with increased Identity benefits – likely due to collaborative endeavours that take place in gardening groups and which are intimately linked to the gardener’s identity, such as learning about new plants, and learning Latin names and growth habits of plants. Garden club members may feel they are contributing to environmental renewal through communal gardening and planting new shrubs and trees, which would also play a part in their self-esteem and sense of self.

Increased social connectedness appears to be a benefit of gardening group membership, as indicated by the significantly higher means on the Social benefits scale for members compared with non-members. The social benefits of gardening as defined by this scale included meeting new people, making and maintaining friendships, and having a shared interest to connect with other people. Gardening groups might be particularly valuable to older persons because of the social contact with other gardeners that membership to a gardening group afforded. Shared gardening interests could help overcome the social isolation some older adults experience, through a greater sense of belonging, community and social support.^19,25

Limitations

While this study contributes to a clearer understanding of the impact of garden participation on older adults’ well-being, the results must be considered in relation to the self-report measures used. The limits to survey use include the difficulty of knowing whether participants understood all of the questions, answered them honestly, or were influenced by how the questions were phrased. Notwithstanding that the self-selected participants’ responding patterns may have varied in some way to the wider population, this study aimed to examine gardeners only, not to compare non-gardeners to gardeners. Future research should be conducted to explore possible group differences.

In terms of interpreting the causal direction of the findings, correlational research does not imply causality, and it is therefore not possible to know whether, for example, participation in gardening activities promotes greater well-being or if the reverse is true, or if the relationship is bidirectional. Furthermore, although this study explored the benefits of leisure gardening for older adults, it is acknowledged that gardening can burden the body and may even injure the older adult gardener; future research is necessary to explore this aspect.

A limitation of the study sample is the overrepresentation of females. Other studies that targeted older adults and examined gardening activities also reported unequal representation of females to males.^11,36 While the current gender bias is consistent with earlier findings, it may be that older women are more devoted gardeners than older men,²¹ or that more women than men respond to survey invitations.^37,38

Declaration of conflicting interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Ethical approval: Institutional ethical approval for this study was obtained from The Human Research Ethics Committee of The University of Queensland, St Lucia, Brisbane Australia.

Funding: The author(s) received no financial support for the research, authorship, and/or publication of this article.

Informed consent: Consent was implied by participants advancing/continuing the survey study after viewing the informed consent page. That is, written informed consent was waived by the Institutional Ethics Committee.

ORCID iD: Theresa L Scott https://orcid.org/0000-0002-6434-7121

1. Begg S, Vos T, Barker B, et al. The burden of disease and injury in Australia 2003. PHE 82. Canberra: AIHW, 2007. [Google Scholar]

2. Berto R.The role of nature in coping with psycho-physiological stress: a literature review on restorativeness. Behav Sci2014; 4(4): 394–409. [PMC free article] [PubMed] [Google Scholar]

3. Peel N, Bartlett H, McClure R.Healthy ageing: how is it defined and measured?Australasian J of Ageing2004; 23: 115–119. [Google Scholar]

4. Lemon BW, Bengtson VL, Peterson JA.An exploration of the activity theory of aging: activity types and life satisfaction among in-movers to a retirement community. J Gerontol1972; 27(4): 511–523. [PubMed] [Google Scholar]

5. Rowe JW, Kahn RL.Successful aging. The Gerontol1997; 37: 433–441. [PubMed] [Google Scholar]

6. Baltes PB, Baltes MM.Psychological perspectives on successful aging: the model of selective optimization with compensation. In: Baltes P, Baltes MM. (eds) Successful aging: perspectives from the behavioral sciences. New York: Cambridge University Press, 1990, pp. 1–34. [Google Scholar]

7. Hill R.Positive aging. New York: W.W. Norton & Co, 2005. [Google Scholar]

8. Lampinen P, Heikkinen RL, Kauppinen M, et al. Activity as a predictor of mental well-being among older adults. Aging Ment Health2006; 10(5): 454–466. [PubMed] [Google Scholar]

9. Ulrich RS, Simons RF, Losito BD, et al. Stress recovery during exposure to natural and urban environments. J Env Psych1991; 11: 201–230. [Google Scholar]

10. Ulrich RS.View through a window may influence recovery from surgery. Science1984; 224(4647): 420–421. [PubMed] [Google Scholar]

11. Bhatti M, Church A, Claremont A, et al. ‘I love being in the garden’: enchanting encounters in everyday life. Soc & Cul Geog2009; 10: 61–76. [Google Scholar]

12. Tilburg WA, Sedikides C, Wildschut T, et al. How nostalgia infuses life with meaning: from social connectedness to self-continuity. Eur J Soc Psychol2009; 49: 521–532. [Google Scholar]

13. Cleary A, Fielding KS, Murray K, et al. Predictors of nature connection among urban residents: assessing the role of childhood and adult nature experiences. Env and Behav. Epub ahead of print 12 November 2018. DOI: 10.1177/0013916518811431. [CrossRef] [Google Scholar]

14. Lewis C.Plants and the community: effects of plants and gardening in creating interpersonal and community well-being. In: Relf D. (ed.) The role of horticulture in human well-being and social development. Portland, OR: Timber Press, 1992, pp. 55–65. [Google Scholar]

15. Ashton-Shaeffer C, Constant A.Why do older adults garden?Activities, Adapt and Aging2008; 30: 1–18. [Google Scholar]

16. Mathers CD, Vos T, Stevenson CE, et al. The burden of disease and injury in Australia. Canberra, ACT, Australia: Australian Institute of Health and Welfare, 1999. [Google Scholar]

17. Hoffman C, Rice D, Sung HY.Persons with chronic conditions, their prevalence and costs. JAMA1996; 276(18): 1473–1479. [PubMed] [Google Scholar]

18. Wannamethee S, Shaper A, Walker M.Physical activity and mortality in older men with diagnosed coronary heart disease. Circulation2000; 102: 1358–1363. [PubMed] [Google Scholar]

19. Haslam C, Steffens NK, Branscombe NR, et al. The importance of social groups for retirement adjustment: evidence, application, and policy implications of the social identity model of identity change. Soc Iss and Pol Rev2019; 13: 93–124. [Google Scholar]

21. Bhatti M.‘When I’m in the garden I can create my own paradise’: homes and gardens in later life. Soc Rev2006; 54: 318–341. [Google Scholar]

22. Glover TD.Social capital in the lived experiences of community gardeners. Leisure Sc2004; 26: 143–162. [Google Scholar]

23. Glover TD, Parry DC, Shinew KJ.Building relationships, accessing resources: mobilizing social capital in community garden contexts (Special Issue: Leisure and Social Capital). J Leis Res2005; 37: 450–474. [Google Scholar]

24. Kingsley JY, Townsend M.‘Dig in’ to social capital: community gardens as mechanisms for growing urban social connectedness. Urb Pol and Res2006; 24: 525–537. [Google Scholar]

25. Townsend M.Feel blue? Touch green! Participation in forest/woodland management as a treatment for depression. Urb Fores Urb Green2006; 5: 111–120. [Google Scholar]

26. Wang D, MacMillan T.The benefits of gardening for older adults: a systematic review of the literature. Activ Adapt Aging2013; 37: 153–181. [Google Scholar]

27. Kidd JL, Pachana NA, Alpass FM.Benefits of gardening: an exploratory study of mid-aged women in New Zeland. Am Horticult Ther Assoc2001; 11: 4–19. [Google Scholar]

28. Laidlaw K, Power MJ, Schmidt S.The Attitudes to Ageing Questionnaire (AAQ): development and psychometric properties. Int J Geriatr Psychiatry2007; 22(4): 367–379. [PubMed] [Google Scholar]

29. Scott TL, Masser BM, Pachana NA.Exploring the health and wellbeing benefits of gardening for older adults. Age Soc2015; 35: 2176–2200. [Google Scholar]

30. Ware JE, Kosinski M, Keller SD.SF-36 physical and mental summary scales: a user’s manual. Boston, MA: The Health Institute, 1994. [Google Scholar]

31. Jaccard J, Turrisi R, Wan CK.Interaction effects in multiple regression. Newbury Park, CA: Sage Publications, 1990, 95 p. (Sage university papers series. Quantitative applications in the social sciences). [Google Scholar]

32. Trigg R, Watts S, Jones R, et al. Self-reported quality of life ratings of people with dementia: the role of attitudes to aging. Int Psychoger2004; 24: 1085–1093. [PubMed] [Google Scholar]

33. Wilson EO.Biophilia. Cambridge, MA: Harvard University Press, 1984. [Google Scholar]

34. van Heezik Y, Freeman C, Buttery Y, et al. Factors affecting the extent and quality of nature engagement of older adults living in a range of home types. Env and Behav. Epub ahead of print 23 December 2018. DOI: 10.1177/0013916518821148. [CrossRef] [Google Scholar]

35. Chiang Y-C, Li D, Jane H-A.Wild or tended nature? The effects of landscape location and vegetation density on physiological and psychological responses. Land and Urb Plan2017; 167: 72–83. [Google Scholar]

36. Kohlleppel T, Bradley JC, Jacob S.A walk through the garden: Can a visit to a botanic garden reduce stress. Hort Tech2002; 12: 489–492. [Google Scholar]

37. Curtin R, Presser S, Singer E.The effects of response rate changes on the index of consumer sentiment. Public Opin Q2000; 64(4): 413–428. [PubMed] [Google Scholar]

38. Singer E, Van Hoewyk J, Maher MP.Experiments with incentives in telephone surveys. Public Opin Q2000; 64(2): 171–188. [PubMed] [Google Scholar]

39. Cheng EH-P, Stebbins R, Packer J.Serious leisure among older gardeners in Australia. Leis Stud2017; 36: 505–518. [Google Scholar]