Written by: Louise Gunderson, Colorado Master Gardener, 2023

Did you know that gardening can help prevent dementia? I don’t know if you have noticed this, but some of the sharpest people I know garden regularly. This effect is so pronounced that it shows up in multiple surveys. I will discuss these surveys and what they have to say about reducing the risk of dementia. While the causes of dementia are not clear, I will list some of the reasons that this might be the case. Finally, I will talk about using farms to help people who have dementia.

For the first study, in the town of Dubbo, in New South Wales, 2805 men and women over 60 volunteered for a study. In 1988, they had a baseline health study done. Individuals returned every two-three years for repeat measurements and sample collection. New individuals were recruited into the study. Some individuals have been followed for up to 28 years. Fortunately for us, the baseline assessment included questions about gardening. In 2006, they found that gardeners had a 36% lower risk for dementia. This was for people who gardened daily, or at least more than once a week. Walking also decreased dementia risk, but only for men.

Another study is the Lothian Birth Cohort of 1921 (LBC1921). This study includes 550 men and women from the Edinburgh and Lothians region of Scotland who took a group administered intelligence test when they were 11. They volunteered to take another test when they were 79. We know a lot about these people, their educational level, their lifestyle, and the changes in their cognitive functioning. The people who gardened frequently had a positive lifetime cognitive change between the ages of 11 and 79

So did gardening help? In a word, yes. But to be fair, it is not the only activity that can help prevent dementia. Yet another study, this time of residents of the Monongahela Valley of Pennsylvania, asked about hobbies, although they did not ask about gardening directly. This study showed that reading books and doing crafts also seemed to lower the risk for dementia. Reading newspapers didn’t help at all. This study found that reading or crafting for more than 3 hours a week significantly improved the effect.

So why might these activities help? The causes of dementia are still unknown. A recent report for The Lancet, suggests that the causes that may be under a person’s control are physical inactivity and social isolation. Another suggestion is that participating in cognitively stimulating activities helps decrease dementia risk. Loneliness has also been implicated.

So, talking specifically about gardening: Gardening involves physical activity. It is also (very) mentally stimulating. In addition, as a member of the Master Gardener community, I can state that it decreases social isolation. I think it checks all the boxes.

However, there is one more reason, that comes from a survey done in England.  According to the author, people who gardened had better general heath, higher levels of physical activity, and better mental wellbeing. They also reported feeling happier.

This effect is so pronounced that in Norway, they have opened daycare farms for people who have cognitive impairments. While these interventions cannot stop the progression of the disease, they have been demonstrated to improve mood, function, and the ability to communicate.

So, go to your garden, and make your brain happy.

Dubbo Study
Nguyen, T.V. The Dubbo Osteoporosis Study. https://rknguyen.wixsite.com/tuan/dubbo-study
Simons et al. Lifestyle factors and risk of dementia: Dubbo Study of the elderly.

Simons, L.A., Simons, J., McCallum, J., Friedlander, Y., ‘Lifestyle factors and risk of dementia: Dubbo Study of the elderly’. Med J Aust. 2006 Jan 16;184(2):68-70.

Lothian Birth Cohort of 1921
Corley, J, Pattie, A, Deary, IJ & Cox, SR 2024, ‘Gardening and cognitive ageing: Longitudinal findings from the Lothian Birth Cohort of 1921’, Journal of Environmental Psychology, vol. 97, 102361.  https://www.sciencedirect.com/science/article/pii/S0272494424001348#bib77

Monongahela Study
Hughes TF, Chang CC, Vander Bilt J, Ganguli M. ‘Engagement in reading and hobbies and risk of incident dementia: the MoVIES project.’ Am J Alzheimers Dis Other Demen. 2010 Aug;25(5):432-8. https://link.springer.com/article/10.1007/s41465-024-00293-2

Causes of dementia
Livingston, Gill et al., ‘Dementia prevention, intervention, and care: 2024 report of the Lancet standing Commission’,The Lancet, Volume 404, Issue 10452, 572 – 628.

Wilson RS, Mendes de Leon CF, Barnes LL, et al. ‘Participation in Cognitively Stimulating Activities and Risk of Incident Alzheimer Disease’. JAMA. 2002;287(6):742–748. https://jamanetwork.com/journals/jama/fullarticle/194636

Freak-Poli R, et al, ‘Loneliness, not social support, is associated with cognitive decline and dementia across two longitudinal population-based cohorts’. J Alzheimers Dis 2022 ;85, 295–308.

Gardening
Siân de Bell et al, ‘Spending time in the garden is positively associated with health and wellbeing: Results from a national survey in England’, Landscape and Urban Planning, 2020.

Day Care Farms
Hotz, Julia, ‘How gardening can help you live better for longer’, BBC, May 12, 2025.
https://www.bbc.com/future/article/20250509-how-gardening-boosts-brain-health