Sow seeds and reap the benefits; how gardening and being in nature can improve your mental health

According to a growing number of studies on the subject, engaging in outdoor activities, gardening, and being in nature in general, can have a positive effect on our mental and​​ physical health, and therefore our overall sense of well being.​​ 

A body of therapies have been developed, predicated on this knowledge that contact with nature can have a deeply therapeutic effect on people. ​​ The therapies are all based on this principle,​​ however go by a number of different names, including “Horticultural Therapy”, “Ecotherapy”, “Therapeutic Horticulture”, “Green Therapy”, and the list goes on.

Fortunately there is no need to get caught up in the semantics of it all, or to decipher which​​ version is more likely to yield positive results, as according to Jude Allen, the founder of SweetTree Farming For All, an organisation which provides therapeutic programmes of this nature,​​ 

“Whether you call it horticultural therapy, ecotherapy, nature therapy, or one of the many other labels…being outdoors – planting, harvesting, having practical connections with nature and animals through a farming or gardening experience – is simply therapeutic by nature.”¹

So what do these therapies involve?​​ 

According to the mental health charity Mind, Ecotherapy​​ is the name given to a wide range of treatment programmes which… help to improve mental and physical well being​​ by supporting people to be active outdoors: doing a range of activities such as gardening, food growing, environmental conservation work, animal care, arts and crafts, exercise, and farming among others, with the support of trained professionals.²

Improving mental and physical wellbeing? This sounds great, but very vague. What exactly are the purported benefits of these therapies? I hear you ask.​​ 

Don’t worry I have dug deep and unearthed a whole rake of them for you, but before we get to them, lets learn a little more about the origin of these therapies and the theories as to why they are proving to be so beneficial.

Although these therapies only appear to have emerged in recent years, it is clear that their roots are grounded in much older, even ancient practices.

Horticultural therapy is an age-old art that, according to the Canadian Horticultural Therapy Association, may have started in Ancient Egypt where Pharaoic doctors would prescribe garden walks for people with/experiencing mental illness. 14th​​ Century Irish monks are also reported to have treated “troubled fellows” using spells of Gardening, and in 1798, social visionary, Benjamin Rush wrote, “…digging has a curative effect on troubled souls.”³

So with​​ this in mind, why then is it only recently that Ecotherapies are being espoused by Professionals?

Well the answer to that lies in the advent of medications for mental illness and their use in treatment from the 1950’s and onwards.​​ ⁴Prior to that, following on from the Victorian Asylum based systems which encouraged and provided garden and farm work, and all purposeful activity in the fresh air, Gardening had remained a common activity in institutions and hospitals.⁵

When the NHS was founded in 1948, the UK was ripe with hospital farms, sanatorium gardens, and more than 16,000 hectares of land dedicated to recovery and respite.⁶

Thankfully, there has been a regrowth of “green care’ projects since the 1980s with the number of projects available to people rising from 45 to 900. These projects today are backed up by sophisticated research and a consolidation of knowledge and should therefore be even more effective and beneficial to those who avail of their programmes.⁷

So now you know a bit of the history regarding such therapies, what are the theories behind them? Why do they have such a therapeutic effect?

One Theory, coined and posited by the famous Harvard sociobilogist, Edward O Wilson, is known as the “Biophilia hypothesis”. Wilson theorises that through our shared evolutionary heritage, humans have a natural affiliation with other living organisms and are instinctively​​ drawn to natural environments.​​ ⁸

This theory is supported by evidence from various studies which suggests that people favour and feel more comfortable in natural environments as opposed to towns and cities.​​ 

Howard Frumkin’s paper, “Beyond Toxicity” cites studies showing a cross-cultural preference for​​ savannah-like landscapes, and stress reduction studies that suggest scenes of the countryside elicit relaxation responses while urban scenes do not.⁹​​ 

Studies of student as well as patient groups suggest that simply viwing certain nature scenes can significantly ameliorate stress within 5 minutes or less​​ (Ulrich, 1999)¹⁰

Other studies have revealed that exercise which takes place in a natural environment produces a greater elevation in mood than that performed in a non-green environment, and faster recovery times with less reliance on potent pain medications have been reported by patients who had a view of a green scene from their hospital ward as opposed to a view of a brick wall.​​ ¹¹

This affiliation with nature is rooted in the evolutionary history of the human species, originating in eras​​ when people lived in much closer contact with nature than most do today.¹²

Wilson’s Biophilia hypothesis is further reinforced by psychoanalyst Carl Jung who when discussing the human need for a relationship with land noted in 1950 that the Americans had suffered from the rapid urbanisation of their country and that as humans we retain in our psyche the primates’ territorial needs.¹³

Herbert W. Schroeder, in his “The Psychological Value of Trees”, also concurs, reviewing the literature and citing aesthetic and relaxation studies, which showed how trees affect our moods, emotions, and​​ enjoyment. He too believes this derives from our evolutionary past…where the African Savannah with its open sight lines, grassy ground plane and scattered trees, reproduced in the modern public park…mirrors an ideal environment for humans providing “prospect refuge,” a place where we can see without being seen¹⁴. Consequently, it meets our primitive psychological​​ needs and is therefore an environment in which we are naturally most comfortable.

Another theory, which explains the cognitive benefits being in nature provides is¹⁵​​ “Attention restoration theory” (ART), ART posits that being in restorative spaces (e.g. gardens) helps to restore people’s directive​​ attention on tasks and thereby improve mental acuity, focusing the mind and reviving the spirit¹⁶

According to this​​ theory, there are two types of attention, “Directive Attention” and “Soft Fascination,”

Directive Attention requires prolonged focus, ignoring distractions and as a result is prone to mental fatigue. An example of a use of directed attention is trying to​​ solve a problem at work, as an individual must intensely focus attention and ignore the surrounding distractions at the workplace.¹⁷

The artificial world, like​​ a downtown city, demands active attention to avoid getting hit by cars, negotiate lights and intersections and navigate around others on the sidewalk. At the same time, city walkers are bombarded by advertisements, traffic and noise. The high-demand attention required when negotiating crowded city streets offers no rest for the weary mind; in fact, it's similar to the​​ intellectual requirements demanded of office workers or of college students.¹⁸

The secondary attentional system, soft fascination, does not require focus and involves effortless reflection. It is proposed by ART to be utilised in natural environments, referred to as restorative environments as they enable the directed attention system​​ to recover from depletion.¹⁹

The cognitive benefits of nature — even if it's just a​​ hint of nature like a poster​​ or a​​ potted plant​​ — are many and have been tallied by a number of recent studies. University of Michigan researchers Marc Berman, John Jonides and Stephen Kaplan wanted to​​ quantify the effects of ART. Students were given long tests of sequences of numbers to repeat in reverse then​​ sent on walks — half the study participants on a nature walk and half on a city walk. Upon re-testing, the nature walkers' scores improved significantly while the city walkers' did not. The experiment was repeated so that each student walked in nature and​​ in the city, and everyone's score was better after the nature walk.

As social scientists explain it, nature engages your attention in relaxed fashion — leaves rustling, patterns of clouds, sunsets, a bird, the shape of an old tree. Nature captures our attention in subtle, bottom-up ways and allows our top-down attention abilities a chance to regenerate. Attention, therefore, is "restored" by exposure to natural environments.²⁰

Alongside ART, runs​​ the Psycho-Evolutionary Stress Reduction Theory (PET). PET suggests that the restorative effects of being in​​ natural environments are derived from the reduction of stress. PET also acknowledges that there are emotional changes involved.​​ 

Although each theory has its own angle with regards to explaining the reason behind nature’s effect, there is a consensus in all three that nature contributes to enhanced wellbeing, mental development and personal fulfilment.²¹​​ 

So now that we know the history and theories behind the therapy, lets take a look at the benefits of it.​​ 

Physical benefits

• According to the Centers for Disease Control and Prevention (CDC), moderate-intensity level​​ activity for 2.5 hours each week can reduce the risk for obesity, high blood pressure, type 2 diabetes, osteoporosis, heart disease, stroke, depression, colon cancer and premature death. The CDC considers gardening a moderate-intensity level activity that​​ can help you to achieve the 2.5 hour goal each week. Additionally, those who chose gardening as their moderate-intensity exercise are more likely to exercise 40-50minutes longer on average than those who chose activities like walking or biking.²²

• A ten percent increase in nearby green space was found to decrease a persons health complaints in an amount equivalent to a five year reduction in that persons age, according to the Gardening Matters nonprofit of Minneapolis page.²³

• Whilst out Gardening you will have more exposure to sunlight. Exposure to Sunlight has possible protective effects against cardiovascular illnesses, (thought to be linked to Vitamin D metabolism, University of Dundee 2007). ​​ It is also essential for bone health. ​​ However, always remember to use​​ sunscreen when necessary to protect your skin from the potentially harmful effects of sunlight²⁴

• A study that followed people in their 60’s and 70’s for up to 16 years found that those who gardened regularly had a 36% lower risk of dementia than non-gardeners, even when a range of other health factors were taken into account.²⁵

• In 2007, university of Colorado neuroscientist Christopher Lowry, then working at University of Bristol in England, made a startling discovery. He found that certain strains of harmless soil-borne Mycobacterium vaccae sharply stimulated the human immune system. It’s quite likely that exposure to soil bacteria plays and important role in developing a strong immune system.²⁶​​ 

• Gardening can help to improve fine and gross motor skills and hand-eye coordination.²⁷

• It can help towards losing weight or maintaining a healthy weight, as garden work can burn between 250-500 calories per hour, depending on the level of intensity of the activity. In fact, one study showed that both men and women who took part in a community gardening project had significantly lower Body Mass Index (BMI) scores than their neighbours who did not take part.²⁸

• While enjoying yourself in the garden, you are also working all the major muscle groups: legs, buttocks, arms, shoulders,​​ neck, back and abdomen. Gardening tasks that use these muscles, build strength, and burn calories.

Besides the exertion involved, gardening has other pluses that make it a  ​​ ​​ ​​ ​​ ​​ ​​ ​​ ​​ ​​ ​​ ​​ ​​ ​​ ​​ ​​ ​​ ​​​​ good form of exercise. There​​ can be a great deal of stretching involved with gardening, like reaching for weeds or tall branches, bending to plant and extending a rake. Lifting bags of mulch, pushing wheelbarrows and shoveling, all provide resistance training similar to weight lifting, which leads to healthier bones and joints. Yet while doing all this, there is minimal jarring and stress on the body, unlike aerobics or jogging.²⁹

• As we age, diminishing dexterity and strength in the hands can gradually narrow the range of activities that are​​ possible or pleasurable. Gardening keeps those hand muscles vigorous and agile without oft-forgotten exercises such as a physiotherapist might prescribe.​​ ³⁰

• Reducing physical pain ​​ – Gardening can be part of a programme that aims to​​ reduce chronic pain or discomfort in patients (e.g.Park et al. 2008). Unruh (2004) reports on a study that showed that gardening helped people with serious health problems cope with their situation when comparing groups of people with and without cancer…the study highlighted a key role of gardening as a coping strategy for living with stressful diseases such as cancer. ​​ According to a survey carried out by Macmillan Cancer Support, 75% of gardeners living with cancer said that gardening during and after treatment helped them manage feelings of depression and sadness. In another online survey of 41 gardeners living with cancer found that 80% say that gardening helps reduce stress and anxiety, and helps take their mind off treatment. Gardening also had a positive impact on the cancer patients’ physical wellbeing. Over 50% say that it helps to give them​​ more energy while one in three say that it helps manage fluctuations in their weight as a result of treatment.³¹

Mental Health Benefits

• The bacterium​​ Mycobacterium vaccae,​​ found in soil, has been credited as being partly responsible for the therapeutic effect of gardening.​​ Known as “the happy bug’, it has been found to promote the production of the brain chemical serotonin, a known mood enhancer. ​​ Through gardening we naturally inhale and ingest this “happy bug” as we would have done when we lived in more rural environments​​ and had a closer relationship with the land. I should add that you are not to go eating or sniffing soil, as this could be detrimental to your health. Just pottering around in the garden is exposure enough.³²

• Exposure to sunlight can also have a positive effect in terms of mood elevation.³³​​ New research suggests that low levels of​​ vitamin D​​ and​​ depression​​ may go hand in hand. The new study included​​ about 12,600 people aged 20 to 90. Researchers measured the vitamin D in their​​ blood​​ and assessed​​ symptoms of​​ depression.

People with the lowest levels of vitamin D were more likely to report​​ symptoms of depression, compared to people with higher​​ blood​​ levels of vitamin D. This relationship was strongest among people with a history of​​ depression³⁴. Healthy exposure to sunlight can help​​ to elevate dwindling vitamin D levels as it​​ triggers the first of three chemical reactions that converts an inactive compound in the skin into active vitamin D.³⁵

• Stress Relief – A study in the Netherlands indicated that gardening is better at relieving stress than other relaxing leisure activities. Two groups of people were required to complete a stressful task. Following this​​ one group was then asked to read for 30 minutes, while the other group was asked to do some gardening for the same amount if time. ​​ The gardening group reported being in a better mood than the reading group and was also found to have lower levels of the stress hormone “cortisol”…According to Clare Cooper Marcus, MA, MCP, professor emerita from the University of California at Berkley, and one of the founders of the field of environmental psychology, one of the reasons why nature may be so successful at reducing stress is that it puts the mind in a state similar to meditation. When you engage in nature, you naturally stop thinking, obsessing and worrying. Your sense are awakened, which brings you into the present moment, and this has been shown to be very effective at reducing stress, says Marcus, drawing on her own observations.³⁶

• Mindfulness – Anyone who is familiar with the concept of Mindfulness will no doubt have felt their ears prick up as they read the previous bullet point. Containing a myriad of sensory stimuli, with its colours, scents, sounds, textures and shapes³⁷, a garden can be the perfect place to practice mindfulness. A place to really​​ observe everything around you, how it looks, smells,​​ feels, sounds and tastes and in doing so anchor yourself completely in the present moment.

• Therapeutic horticulture in clinical depression was studied by Gonzalez et al. (2010) in Norway…results showed a​​ clinically relevant decline in depression in 50% of participants and the participants maintained their improvements in scores at a 3 month follow up.

• Traditionally men are more reticent when it comes to talking about their mental health and are less likely to seek help. They may fear the stigma surrounding such issues or fear being seen as “unmanly”. This is a sad situation as it can leave them suffering in silence. Thankfully, Ecotherapies seem to have helped to break down this pattern somewhat as Mind found that on average 56% of attendees at their Ecotherapy projects were men. At some projects the percentage of men attending was even higher, for example at “Go Wild” in Taunton, 82% of participants were men. They reported liking the fact that it was not presented as a traditional “talking therapy”, yet once involved they found themselves talking and feeling better for it.³⁸

• Minds findings in their evaluation of their Ecominds projects –​​ 

  • 62% of participants experienced an increase in their self-esteem after involvement in the programme. According​​ to the American Horticultural Therapy Association…”For many patients whose conditions (and treatments) have rendered them feeling passive and dependent, having living plants to nurture creates a role reversal, placing the patient in the care giving role which often engenders confidence and a renewed sense of purpose.³⁹ ​​​​ According to Teresia Hazen, who oversees a horticultural​​ therapy programme in Oregon, USA, “For patients who find themselves restricted by a disability, even the simplest gardening experience - such as growing a potted plant from a cutting - gives them a feeling of control.”⁴⁰

  • 63% experienced a rise in their positivity scores over the course of the programme and the average percentage change for participants was an improvement in positivity of 40%.

  • 75% of participants experienced an improvement of mood, which included a reduction in feelings of anger, confusion, depression, fatigue and tension, and an increase in vigour. This improvement in mood was experienced by participants of all genders and ages, and for all project types.

  • 61% of participants experienced an increase in terms of their connection to nature. As we discussed earlier, being in nature and feeling connected to it​​ meets our primitive psychological needs and thus promotes good mental wellbeing.​​ 

  • 57% of participants saw increases ​​ in their ‘perceived health’.

  • Findings showed a statistically significant increase in most (57%) participants’ social engagement and support​​ scores from the beginning to the end of their involvement with the Ecominds project.

  • By the end of the programme, 59% of participants said that they felt they belonged to their immediate community.

  • 50% of participants in the within group study experienced​​ an increase in importance of eating healthy food scores and 53% experienced an increase in exercise importance scores. Demonstrating that Ecotherapy can help to promote the living of a healthier lifestyle.

  • 57% of participants experienced an increase in the feeling that being with others is important,​​ implying that they valued spending time with others as part of the Ecominds project. To add to this, 57% felt that there were more people in their lives who cared about them and that they met more often with friends and relatives.​​ 

  • 81% showed an increase in the frequency of getting involved in other community activities, after being involved in the Ecominds scheme.

• If you read my previous article regarding the benefits of volunteering on mental health, you will​​ know that the isolation, loss of social roles and difficulty those with mental health Conditions experience, regarding using their time meaningfully⁴¹, can all serve to aggravate things further by potentially leading to unemployment, a lack of confidence and motivation, an inability to concentrate, difficulties in trusting people, an inability to make or​​ sustain friendships, and feelings of isolation, frustration and anxiety.⁴²​​ It is clear from the findings of these studies that Ecotherapy can go towards rectifying these issues, providing meaningful activity, a sense of purpose and achievement, improved confidence and self esteem, improved concentration, a social environment allowing for the making of friendships and a greater support network, a potential pathway to employment etc.

• Benefits for sufferers of Dementia and Alzheimer’s disease – The UK National Institute for Health and Care Excellence (NICE) recommends that care plans for Alzheimer’s disease and Dementia address activities of daily living that maximise independent activity, adapt and enhance function, and minimise need for support. (NICE, 2011). The Garden and the activity of gardening provide a non-pharmacological approach to address these goals.

• A number of studies have​​ shown the benefits of therapeutic gardens and horticultural activities for patients with dementia...reported benefits including,​​ reduction of pain, improvement in attention, lessening of stress, modulation of agitation, lowering of as need medications, and​​ antipsychotics and a reduction in falls…Yasukawa (2009) showed improvements in communication, engagement, behaviour and cognitive abilities…D’Andrea et al. (2007) reported that horticultural activities resulted in maintenance of memory and sense of well being..Connell et al. (2007) reported improvements in sleep patterns and a decline in verbal agitation….Hewitt et al. (2013), noted that structured gardening over a period of 12 months had a positive impact on the wellbeing, cognition and mood of people with young-onset dementia.⁴³​​ 

Other more practical benefits

• Gardens can​​ increase property values – Should you decide to get green fingered in your own garden, having a nice well kept garden can help to increase the value of your property.

• Reduced grocery costs – If you grow fruits and vegetables fit for consumption then this​​ could help to drive down the costs of your grocery bills as you will no longer need to add such items to your shopping list.

• Ecotherapy could lead to paid employment – Ecotherapy offers a pathway to employment, education and training especially for those who have been unemployed for a long time or have other challenging life circumstances, reducing welfare and benefits costs and increasing tax revenue. Being out of work is strongly linked with poor mental health and wellbeing and people with mental health problems can find it very hard to get back into work. Mind’s Ecotherapy services helped people can valuable employability skills such as timekeeping and team work, it afforded them the opportunity to practice communication skills and helped them to become​​ motivated. Some services also helped participants to find work experience placements, to write CV’s, to complete application forms and get job interviews with associated businesses. One project in particular, “Growing Skills,” which offered a horticultural​​ training course and related work experience saw 60% of it’s participants go on to employment or further education and training. The Ecominds scheme as a whole managed to help 254 participants to find full-time employment.​​ 

How to get involved

So how can​​ you get involved and become a budding gardener? Well due to the positive findings reported in Mind’s research into their Ecotherapy projects, they are really pushing for Ecotherapies to be made more readily available to the public as an intervention in the treatment of mental health.​​ 

As it stands currently, 36% of GPs would refer their patient to an Ecotherapy project if there was one in their area.​​ 

​​ Green fingers crossed, this will increase as through Mind’s Ecotherapy initiative more projects should​​ shoot up and GP’s should become more aware of the benefits of Ecotherapy, making it more likely that they will be willing and able to refer patients to such projects.

If you are interested in giving it a go, speak to your GP first and see if there are any​​ projects in your area that he would be willing/able to refer you to. Failing this, a quick Google search should reveal if there are any such projects in your area that you could contact directly.

If there are no projects available in your area, don’t despair. Although it is probably better to join a group of some sort, so as to experience the social component of gardening or outdoor activities, just doing some gardening in your own garden or going for a walk in a green area with a friend or family member​​ is great too.​​ 

Conclusion

Research has clearly shown that Ecotherapies provide a panoply of benefits for those dealing with mental health conditions. Weeding out the negative effects of poor mental health, creating the opportunity for good mental health​​ to blossom, they really are worth considering as an adjunct to your primary treatment. Of course I would however always recommend that you discuss this fully with your treatment provider first.​​ 

Bibliography/Referencing

Darnton. J, Maguire. L, ‘What​​ are the physical and mental benefits of gardening?’ Michigan State University Extension, 19 May 2014,​​ http://msue.anr.msu.edu/news/what_are_the_physical_and_mental_benefits_of_gardening. (accessed 20 October 2015).

Eliades. A, ‘WELLBEING GARDENING-GARDENING FOR THE BODY,MIND & SPIRIT’, Permaculture Research Institute, 5 June 2013,​​ http://permaculturenews.org/2013/06/05/wellbeing-gardening-gardening-for-the-body-mind-spirit/. (accessed 20 October 2015).

Stuart-Smith. S, ‘Horticultural therapy: Gardening makes us feel renewed inside’, Telegraph, 31​​ May 2014, ​​ http://www.telegraph.co.uk/gardening/10862087/Horticultural-therapy-Gardening-makes-us-feel-renewed-inside.html. (accessed 20 October 2015).

Thrive, ‘What is Social and Therapeutic Horticulture?’,​​ http://www.thrive.org.uk/what-is-social-and-therapeutic-horticulture.aspx. 2015. (accessed 20th October 2015).

Slawson. N, ‘Nature’s pill: ‘ecotherapy’ for mental health problems, says charity’, Positive News, 7 February 2014,​​ http://positivenews.org.uk/2014/wellbeing/health/14643/natures-pill-prescribe-ecotherapy-mental-health-problems-charity/. (accessed 20 October 2015).​​ 

Mind, ‘New Research shows benefits of ecotherapy for mental health and wellbeing’,​​ http://www.mind.org.uk/news-campaigns/news/new-research-shows-benefits-of-ecotherapy-for-mental-health-and-wellbeing/#.ViaqGoe4mu4. 2013. (accessed 20th October 2015).

trellis, ‘Therapeutic Horticulture: theory and evidence’,​​ http://www.trellisscotland.org.uk/factsheets. 2013. (accessed 20th October 2015).

Care Farm Crew, ‘BBC’s Monty Don: Gardening as mental health therapy’, ​​ http://www.sweettreefarmingforall.org.uk/about-us/. 2015. (accessed 20th October 2015).

James. O,’Ecotherapy: how does the great outdoors improve mental health?’, the guardian, 17 June 2014, ​​ http://www.theguardian.com/lifeandstyle/2014/jun/17/ecotherapy-how-outdoors-improve-mental-health-parks-wilderness. (accessed 20th October 2015).

Bushak. L, ‘Benefits Of Ecotherapy: Being In Nature Fights Depression, Improves Mental Health And Well-Being’,​​ http://www.medicaldaily.com/benefits-ecotherapy-being-nature-fights-depression-improves-mental-health-and-well-being-261075. 2013. (accessed 20th​​ October 2015).

Wikipedia, ‘Horticultural therapy’,​​ https://en.wikipedia.org/wiki/Horticultural_therapy. 2015. (accessed 20th October 2015).

greencircle, ‘Horticultural Therapy Benefits’,​​ http://www.greencirclegarden.com/horticultural-therapy-benefits/. 2015. (accessed 20th October 2015).

Gordon. G, ‘Proof: gardening is healthy’, Daily Mail,​​ http://www.dailymail.co.uk/health/article-193859/Proof-gardening-healthy.html. ​​ (accessed 20th October 2015).

Mountford. M, ‘Health Benefits of Horticultural Therapy’, Issue 65 June, 2001,​​ http://www.positivehealth.com/article/herbal-medicine/health-benefits-of-horticultural-therapy. (accessed 20th October 2015).

Mind, ‘Feel Better Outside, Feel Better Inside: Ecotherapy for mental wellbeing, resilience and recovery’, 2013,​​ http://www.mind.org.uk/media/336359/Feel-better-outside-feel-better-inside-report.pdf?ctaId=/about-us/policies-issues/ecotherapy/slices/read-the-report/. (accessed 20th October 2015).

Bragg. R, Wood. C & Barton. J, ‘Ecominds effects on mental wellbeing: An evaluation for Mind’, 2013,​​ http://www.mind.org.uk/media/354166/Ecominds-effects-on-mental-wellbeing-evaluation-report.pdf. ​​ (accessed 20th October 2015).

Garden Organic and Sustain, Schmutz. U, Lennartsson. M, Williams. S, Devereaux. M & Davies. G, ‘The benefits of gardening and food growing for health and wellbeing’, April, 2014, ​​ http://www.sustainweb.org/resources/files/reports/GrowingHealth_BenefitsReport.pdf. (accessed 20th October 2015).

Rogers. K, Encyclopaedia Britannica, ‘Biophilia hypothesis’,​​ http://www.britannica.com/science/biophilia-hypothesis. 2015. (accessed 20th October 2015).​​ 

Krisch. K, Positive Psychology Programme,​​ ‘Attention Restoration Theory & Nature: Let’s Solve Problems…’​​ http://positivepsychologyprogram.com/attention-restoration-theory-nature-lets-solve-problems/. 2014. (accessed, 20th​​ October 2015).

McKinney. J, ‘Thoreau was right: Nature Hones the Mind’, Pacific Standard, 11 Jan 2011,​​ http://www.psmag.com/nature-and-technology/thoreau-was-right-nature-hones-the-mind-26763. ​​ (accessed, 20 October 2015).

Iannotti. M, About.Com, ‘Is Gardening Good Exercise?’,​​ http://gardening.about.com/od/allergiesarthritis/a/Garden_Fitness.htm. ​​ 2015. (accessed 20 October 2015)

Jacobs. R, eartheasy, ‘6 Unexpected Health Benefits of Gardening’,​​ http://learn.eartheasy.com/2014/09/6-unexpected-health-benefits-of-gardening/. 2014. (accessed 20 October 2015).

Mann. D, reviewed by Nazario. B MD, WebMD, ‘Low Levels of Vitamin D May Be Linked to Depression’,​​ http://www.webmd.com/depression/news/20120110/low-levels-vitamin-d-may-be-linked-depression. (2012). (accessed 20 October 2015).

​​ Batra. S, ‘Does the Sun Give People Vitamin D?’,​​ The San Francisco Chronicle, 2015,​​ http://healthyeating.sfgate.com/sun-give-people-vitamin-d-4942.html. (accessed 20 October 2015)

​​ Howlett. S, ‘Volunteering and mental health: a literature review,’ VAJ 2004 (vol6,number2),​​ Institute For Volunteering, 2004. (accessed 13 August 2015).

Institute For Volunteering, ‘Volunteering and Mental Health,’ Institute For Volunteering, 2003. (accessed 13 August 2015).