Wellbeing Gardens and Biophilia with Dr. Lauriane Chalmin-Pui
Welcome to the Green and Healthy Places podcast, in which we explore the themes of wellbeing and sustainability in real estate and interiors today.
I'm your host, Matt Morley, founder of Biofilico healthy buildings and in this episode is episode (50) I'm in the UK talking to Dr. Lauriane Chalmin-Pui, a wellbeing Fellow at the Royal Horticultural Society. The RHS is the UK's leading gardening charity.
Dr. Lauriane Chalmin-Pui completed her PhD at Sheffield University where she conducted research on how domestic gardens can support physical and mental health via exposure to plants and wildlife. So if you're a regular listener to the podcast, you'll see the angle of where our conversation might go connecting gardens with biophilic design in interiors and buildings.
Our discussion covers topics as diverse as
wellbeing gardens, also known as healing gardens
planet friendly low environmental impact gardening
environmental psychology as it relates to gardens
the emotional, physical, and even social benefits of gardening and generally tending to plants
the benefits of biophilia for our microbiota via direct exposure to soil and earth
her forthcoming research publication on the role a garden’s colors and scents can play in creating a positive impact on human health and wellbeing.
Matt Morley
Thank you so much for being here with us today. I'd really love to start with a an initial question on the concept of environmental horticulture, which is your area of expertise. Could you give us a brief intro to that?
environmental horticulture
Dr. Lauriane Chalmin-Pui
Yeah. Hi, Matt. Thanks a lot for having me. So I'm a postdoctoral fellow at the Royal Horticultural Society under the University of Sheffield. And I'm physically based in Wisley, in the hilltop home of gardening science, and I'm in the environmental horticulture team.
So we're primarily primarily concerned with improving our understanding of the interactions between soil, plants, water, and people. This includes carbon, water and nutrient cycles for both outdoors and indoor plants, and how they're impacted by people, of course, as well as the impacts of gardens and gardening on human health and wellbeing. All of these functions are interconnected. And that's why the word ‘environment’. And of course, as I'm sure you'll know, it's all in the context of accelerated urbanization and land use change the biodiversity and climate crises.
We're having more frequent extremes of temperatures and precipitation, which then has the knock on effects on climate on the hydrological cycle and biodiversity on soil health. And our environmental horticulture team is composed of different specialists in these areas.
So we've got horticultural scientists, the soil and climate change scientist, water scientist and fellows like me on tree traits and ecosystem services, for example, in sustainability, of course, research technicians as well. So our primary question in all of that is about the practical interventions that gardeners can apply to reduce their gardening footprint and then also improve environmental health and human wellbeing.
Biophilic design
Matt Morley
It strikes me that there's a parallel between the work you're doing, which is very much academically driven around these outdoor spaces, and biophilic design - some of the principles that apply to my world in terms of creating greener and healthier buildings, where we're constantly balancing those twin demands around our impact on the environment, and the potential positive or indeed negative impacts on the occupants of a building.
You mentioned, climate change. I know it's not perhaps your first specialism but just give us a very broad intro to sustainable gardening, how can gardening be anything but sustainable?
Sustainable gardens
Dr. Lauriane Chalmin-Pui
Right, so I think in terms of a garden sustainability is very much about environmental resilience, whether that's indoors or outdoors. And there's many ways in which we can actually have a negative footprint, if you will. So if you're using peat based compost, for example, that is depleting peat bogs, which are a very important ecosystem and also a carbon store. So it really depends on the practices. And there are so many different ways of garden gardening.
When we think about surface area, we might think that oh, domestic gardens, for example, are quite small and won't necessarily have a big impact. But residential gardens comprise about 30% of Great Britain's total urban area while the total area of UK domestic gardens is about 700,000 hectares, which is equivalent to more than 90,000 football pitches. So it's quite a large area.
Carbon sequestering trees
One positive thing for example a gardener can do is to plant a tree, in their garden or community or school or wherever. And if every gardener did that we would be storing huge amounts of carbon. But one further thing to think about when we think about environmental horticulture, again, is that we shouldn't necessarily just plant a certain tree because it's sequester is more carbon, because we would loose diversity if we planted the same tree. And the goals of a garden are different for example, the goals of a woodland or an agricultural patch.
We're operating on different timescales. So in a timber woodland, you might want to plant a tree that sequesters more carbon in that shorter timescale before it gets cut down. But in a garden, you're probably not anticipating to cut down your tree within the next 10 years. So you might want to choose a tree that encourages that slow growth and sequester carbon over time and storing it in the tree.
Water efficiency for sustainability
Then there are water practices. So whether you are irrigating your garden from mains water will be very different to if you are harvesting rainwater, creating permeable as much permeable surface area and just different practices of how you water, how you feed your soil. There's definitely lots of scope that any gardener can do in their home and for us at the RHS how we can influence the horticultural industry, the government and how we can promote these different, more sustainable behaviors. And then, of course, we have our own gardens that, you know, we have our own operations that are going in here. So we're also trying to improve that.
sustainable green buildings
Matt Morley
Great, okay, so you've brought up a couple of things there. I think the one point that just occurred to me as I was listening to you is very much same principles, when we look at, say, putting in a green roof on a, on a building as part of a sustainable real estate plan.
You know, we're trying to achieve many of the same outputs that you've you've just described and also deal with many of the same issues around for example, irrigation and how rainwater collection can just effectively reduce overall water consumption and lower irrigation systems and shear escaping and things like that.
wellbeing gardens
You mentioned the RHS and its role so for those who are perhaps not familiar with it, or anyone listening from outside of the UK, we're Royal Horticultural Society, what is the overall aim you're obviously specialists in Wellbeing within the health and planetary aspect of the Environmental Horticulture team, but the RHS itself? How does your team fit into the wider picture? And what are the aims and objectives of your teamwork over the course of a year?
Dr. Lauriane Chalmin-Pui
Right. So the Royal Horticultural Society is the UK is largest gardening charity. And so it's, it's all about that horticultural knowledge. So we have an advisory service members can call in and ask questions. It's about inspiring people to, you know, do the best and their guidance. And it's about promoting that horticultural industry as well. And within our team, it's very much the science so the evidence base for this for for all of this the different initiatives, we've also got a community outreach team, for example, who work in areas that may not have that safe and quality access to green spaces.
planet friendly gardening
One of the campaigns at the moment is a planet friendly gardening campaign. So this is exactly the kinds of things that we're talking about. And the aim of that is to help gardeners make the most of the physical and emotional benefits of gardening both for the planet And for ourselves? What was the next part of your question?
healing gardens
Matt Morley
So you mentioned? Well, you, you've just tied them both in next you mentioned the emotional benefits of gardening. And you also mentioned that the IHS had been working on some of his own gardens. And doing some research for our conversation, I saw that I think it was four of these sort of health and wellbeing gardens going up. So let's dig into that a little bit. So the emotional benefits from your evidence based perspective, like, how do you quantify those? How do you provide evidence for them? And what are the sort of broad buckets in terms of those emotional benefits? We're presumably talking more about mental health and well being?
biophilia for mental wellbeing
Dr. Lauriane Chalmin-Pui
Yes, so there is a wealth of evidence on the mental, but also the physical and the social health benefits of gardens and gardening. And this is it's a relatively new field in science, it started picking up in the 80s in the field of environmental psychology. So there is an and it's been growing ever since. And I think the COVID pandemic, one thing that it has alerted us, other than, of course, you know, medical infections, is the importance of green spaces.
Biophilia research
So I think it's really picked up. Most people now understand this, if you tell them about the mental health impacts of a garden, they're not going to look at you like you're crazy. So I think that it's really been building but in the 80s, one of the first studies was by an environmental psychologist called Roger Ulrich, and he had a sort of natural experiment where he was looking at patients recovering from gallbladder surgery.
In the hospital, one wing of the hospital had a view of trees, the other wing of the hospital, the windows had a view of a brick wall, and other buildings. And he saw that the people who were having rooms with a view of the trees were recovering a couple of days faster and being discharged a couple of days earlier than the patients with the view of the brick wall. They were requiring less painkillers, and they were less grumpy with the nurses. So that that was the real seminal studies.
Since then, there have been theories that have been proposed. So the likes of attention restoration theory by Stephen and Rachel Kaplan stress reduction theory which was developed by the same Roger Ulrich. And I started this research with my PhD in 2016. And really, in these past five, six years, it's it's really grown a lot to the wealth of evidence on mental physical and social health.
So for example, the things we can really look at are symptoms of depression, anxiety, so that's been shown to be reduced with gardening. There you can also look at pleasant and unpleasant emotions and the frequency of them. You can look at mental health during the COVID lockdowns for example, they've been quite extreme scenarios, but quite common scenarios now for many of us, we can look at general scales of well being we can look at reported stress, feminine.
Physiological benefits of biophilia
So that's a self reported psychological perspective. But we can also look at physiological stress regulation. So one of my studies, for example, looked at cortisol, which is the body's main stress hormone. And I found that the presence of plants and small front gardens did actually have an impact on the residents cortisol patterns on the daily basis.
So there's all sorts of things you can there's also in terms of physical health, you can look at positive habits forming around diets and physical exercise, there have been studies showing that greener spaces are more likely to encourage active travel, so such as walking and bicycling, for example.
Green exercise in the garden
Gardening regularly also has been shown to reduce the risk of fracture. So like limb fractures, and it's it's an adaptive form of physical exercise. So as one grows older, and perhaps physical abilities change, it is an activity that one can keep up with, as opposed to maybe running that is not as adaptive. And we're learning more and more about the importance of exposure to microbial diversity. So that's through soil and vegetation, small microbiota, very small organisms that are found on the skin and in our gut depending on what we eat, and that will have a knock on impact on our immune system.
social health benefits from gardening
Finally, social health, which does often get forgotten is linked to things like a sense of community, a sense of belonging in one's area, making friends, feeling feeling connected with the world around us. And that will have a knock on impact on our sense of self esteem and creativity and having, you know, a kind of meaningful occupation to do. So there's, there's lots of things, really, and it's only growing. Of course, each of these studies are done in particular context of particular populations. So there's always more to do.
Biophilic design research studies
Matt Morley
The thank you for that. It's, it's so interesting to see the crossover, you know, that Ulrich study, which I think was in sort of the early 80s. And not that much seems to have been done since then, if I'm honest, we all go back to that one study of X number of patients in a hospital room, but even in the biophilic design space, it's really the seminal piece that we all refer to, and then again, into the sort of the ATR and that are SRT studies, or concepts and theories biophilic design.
What I'm seeing is that it has much more of a passive component, I think what's coming through from what you've just said, is there's this active piece. And I think the key word, there might be gardening, rather than just exposure to plants in nature.
So I often think about that in terms of forest bathing, where there is an element of engagement with nature. And I think with gardening, you're taking it a level further, because you're then prompting exposure to the plants and therefore tapping into that sort of immune health microbiota. And then that social peace around community and engagement is immediately suggesting that perhaps a like a rooftop garden in a residential building, for example, or an office even would have far more or perhaps a wider application in terms of the physical benefits than just bumping up the number of air purifying plants in reception, for example, I think that's, it's a really striking piece of of, of insight that perhaps biophilic design, yeah, maybe struggled to get to, because it tends to be more about introducing these elements into a space and then accepting that people will just sort of passively take in their surroundings and, and hope for the best gardening is much more about engaging with the garden and, and playing an active role in it clearly, that's the main difference. Right?
Dr. Lauriane Chalmin-Pui
Right. So there's two, the active and the passive engagement of the plants, you're absolutely right to, to draw those two as key differences. And of course, when you are gardening, you do have that added element of creativity of being able to shape the environment that's around you, which psychologically is very linked to to, to a feeling of control. And when we look at how that might be impacting, I mean, often a lot of the ills that we have, are often around uncertainty and lack of control.
So when someone can control something that will usually have quite a lot of benefits. However, I do disagree with you, but the more passive exposure to plants doesn't have much impact. And that is kind of negligible because there are more and more studies, including one of my own, that, even just that that passive exposure of having something nearby so whether that's in an office or in a home or just outside of the home, that very frequent access does have an impact on perceived stress on perceived well being but also on this cortisol patterns, which I mentioned earlier.
So I did a study that we we found the whole street, that garden, they had front gardens, so that the physical space between the House and the street or front yards if you're in North America, that were previously paved over and so I did an intervention where I added plants to them. And I studied the residents there of over the course of a year. And we found that before the interventions only intervention only 24% of the residents had this healthy diurnal cortisol pattern. So it healthy physiological stress regulation, and then after we added the plants this increase to 53%, suggesting that those individuals had better physiological stress regulation in their bodies, which probably had a link to their mental health.
Matt Morley
That was your four year research project with the University of Sheffield. Is that the one Yes,
Dr. Lauriane Chalmin-Pui
most of those people were not actively taking care of. So they were to planters, with some ornamental plants in them. They were self watering containers. So that was a store of water underneath. So the participants barely even had to watch them. It was in Salford, where it rains a lot. Though for the vast majority of these people, there was no real active gardening engagement, but they still got those benefits.
Matt Morley
And you went with ornamental plants. Is that so what were the specifics of that we're looking for color. Do you think what you obviously went for what you would imagine would create the most positive benefits? Right? So is that about aesthetics? Is it about painting the rainbow with the flowers and the plants that are out there? Or what suggestions would you have in terms of trying to bring a little bit of that in?
Dr. Lauriane Chalmin-Pui
Sure. So interestingly, in that experiment, I didn't go for what I thought would have the most benefits, I wanted to isolate as many factors as possible. So when you're doing a science experiment, I didn't want to kind of conflict I didn't want to put food for example, because then it could be argued that the people were having a higher well being because they were deriving other benefits, maybe having a cheaper food bill, if they were getting some harvests from it. I didn't want to go for anything to aromatic that might, you know, lift up spirits in other ways. I wanted to go for something not too exotic either, that would provide a huge novelty factor.
For example, I wanted to go with plants that are quite normal. So all found in regular garden centers and quite familiar to people. So we had a mix of some bedding plants, some shrubs and climbers. And the focus also was of course, the climatic conditions of of Salford, but something that was easy to know, maintenance and that self watering container. But yeah, I mean, we did go for something.
So we went for a kind of purple palette we had asked for. We had asked the residents beforehand if they had anything they particularly didn't want. But then beyond that, they were happy to go with anything. So they were Viola's petunias as alias clematis, then spring bulbs, so daffodils, snowdrops and practices. Yeah, so So quite a quite a familiar range of plants.
Matt Morley
And I know you recently were involved in the health and horticulture conference 2022, and your particular presentation, there was around research and community. So with those two, research a community, the city and the street. So were you there talking about that subject? And have you evolved or thinking since the end of the research projects? What were the sort of key messages you were communicating there to the audience?
Dr. Lauriane Chalmin-Pui
Yeah, so the RHS, health and horticulture conference that was on the 17th and 18th of March was very much part of my own research agenda. Were going beyond the actual logistics of the research itself, we really do want to play that role in bringing people together. So one of the things we've found is that the horticulture industry itself doesn't necessarily fully recognize these health and wellbeing impacts and the evidence base for it.
And the health and social care sector as wide as I can cast that net doesn't necessarily have the skills and understandings to really have that Win Win effect. And then of course, around and associated that to that you've got professionals in urban planning and in the built environment, like yourself, and, and there's so much more.
So really, what we wanted to do was bring people together and share that knowledge and my own talk as as part of that was, yeah, so titled, research and community and that was really to tie in the importance of people in the development and the application of that research.
So how can we achieve the integration between science and and I mean, to call it outreach, but knowledge dissemination and sharing, and what I meant by the city and the street level, was because it refers to the scale at which physical, mental and social health often operate for individuals and for communities, especially when we're thinking about green and cultivated spaces and domestic gardens.
So for the average individual, their well being will be based on you know, to a certain extent their genetics and their lifestyle and things like that. Of course their family their Friends, but then in terms of a spatial scale, it will be the city and the street, their home, their workplace, their school.
And it the aim of the conference all together is to improve the recognition of gardens and gardening as that as a valuable public health asset and as a resource that can contribute to promoting better health for everyone, but also reducing that incidence of poor health that are generally well seemingly well population as well as for specific groups of people who might need more targeted interventions or more specific support to access safe green spaces.
Matt Morley
And from the outputs of the conference, and but also based on your own knowledge. When one thinks of, say, healing gardens in cancer care homes, for example, like in the Maggie's care centers, where they create gardens that are intended to be spaces for cancer patients to on some emotional level to heal. Is there a is there a playbook emerging in terms of the way to maximize the space to get the most out of it from a scientific perspective, in terms of those mental well being benefit mental and physical? Benefits? Are there key principles that are starting to become clear? Or is that still a work in progress?
Dr. Lauriane Chalmin-Pui
From the design element, I'd really recommend the work and the book of Claire Cooper Marcus, who has looked at therapeutic garden design, and she has based a lot of her findings on post occupancy evaluations. And it's it's really wonderful, she not only looks at the impacts on patients and their visitors, but also quite importantly, on the staff who are working at that hospitals who often do have quite tough frontline jobs.
Again, we've seen that even more with the pandemic. But actually, there's not yet any scientific evidence base. So I have a PhD student who's just been citing out doing a scoping review for exactly what you're saying. And looking at the scientific literature, she's not really found much that has any kind of quantitative evaluation of this. So it's all quite qualitative, subject to the designs, of course, in very different contexts, it can be relatively straightforward, I think, to spot a bad design, something that just isn't used by people, you might have a garden space that, you know, has metal benches in a hot climate.
So of course, nobody's going to sit there, that's very easy to pinpoint. But then, in terms of really leveraging and optimizing what we do know, that scientific approach isn't there yet. And that is the case for these kinds of hard features, let's say but also for plants. So the role of scent of color of symmetry, for example. And often in when you're looking at planting design handbooks, there isn't, there's often an approach that's based on choosing the plants for their function for the wider ecosystem. And then the last thing is kind of aesthetics and sensory properties. And of course, all three of them are very important.
But that last point, is generally just completely subjective. And based on personal taste of either the garden designer, or if they've done a sort of consultation, focus group with the with the future and potential users of the place. But there's not. Yeah, there's not yet that scientific approach. So that's what we'd really like to get to one of our goals at the RHS is to create an evidence based blueprint for wellbeing gardens, whether that is in a hospital context or a a residential context, the school context, the prison context, those kind of model to go on that is based on scientific evidence
Environmental Psychology
Matt Morley
which would then be so useful for various other sectors, including my own. That's what's I think, so powerful about the work that you're doing is that it can then be leveraged in other sectors too, because it has this sort of spillover effect. You mentioned. Color and scent. I know you've been doing your own research on that. It may be too early to, to speculate on the outcomes of it, but what's your initial hypothesis in terms of the role of color and scent on stress and well being from a garden context?
Dr. Lauriane Chalmin-Pui
Yeah, so I've started doing some indoor experiments and we'll be doing outdoor ones as well to kind of have a multi pronged approach to understanding this. Essentially, what we've got outdoor for example, in the wizzley RHS Bisley garden in Surrey, we've got a wellbeing garden, which has been designed by Matt Keatley as a living laboratory. So it's got these different features, there is an area of running water for example, there is an area of Stillwater there's an area of plants and flowers that are deeper reds and oranges. And then an area that has more whites, pale pinks, pale yellows.
So the wellbeing garden there is, as I said, not based on any scientific conclusions, but it's based on scientific hypotheses. Um, and then it gives us the space to test them out. So one of the hypotheses for example, is the impact of color on an emotional responses to different colors. So in psychology and marketing, we know for example, that the color red can evoke certain different emotional responses. So be that power or anger or love. And often these kinds of things will be mediated, of course, by cultural and individual idiosyncratic experiences. But there's no research so far on whether those color stimuli, whether they have the same emotional responses when they're in a natural setting in a garden and on a plant.
And so one of the hypotheses following that psychological theory is that the reds and the warmer colors might be more arousing when we when in terms of arousing emotion, so they're the more active emotions, like excitement and invigoration. And anger as well is excited is an arousing emotion. And then when we look at the cooler colors, the whites, the pastels, the blues, whether they would be more calming. And of course, when I think often when we think of a well being garden, or a therapeutic garden, or a healing garden, or whatever you want to call it, I think most people automatically think of relaxation under lower stress.
But actually, that's not necessarily what we need. As humans, we don't want to just be relaxed all the time. And guidance can be a place for us to experience our full range of human emotions. So sometimes we want to be really stimulated. And so that's part of the design and whether that's through color that I've been talking about or a sense. So we know that sense, like rosemary, for example, there have been tests on rosemary essential oil that has increased alertness and cognitive attention.
aromatherapy for wellbeing design
So you know, if you do a little kind of little cognitive tests, people have scored higher when they've had some rosemary essential oil next to them versus without. So there are so many ways in which the planting palettes of a garden can influence and if you've got a space that can be, for example, divided into two areas very crudely, you can have one that is less arousing one one that is more arousing, and depending on how you as an individual are feeling that day, you can go and surround yourself in an environment that suits what you need, what you want, how you're feeling. And that will help you regulate your emotions in a in a healthy way, rather than suppressing anything.
Matt Morley
Well, if you can get to it, that type of insight would help anyone working in the biophilic design field to say create know how to adapt the interiors in a space, for example, in an office environment where perhaps it is more about cognitive performance and alertness and concentration productivity, versus, say a quiet room space within a large office, which was more about the end to that Yang.
So then about calming and restorative, because I think, yeah, we just don't have the scientific base basis for that. I think we're often doing it more on instinct. And I was going to close if I may, by a question on that, Rob, perhaps less instinct more on an angle around evolutionary psychology. I just wondered from your perspective, which is clearly science based.
evolutionary health perspective
Is there any room for an evolutionary psychology approach that says, well, perhaps some of what we're dealing with here is, is about as much as anything our genes, our history, our evolution on the planet in tune and connected with nature? Is there space for that? Or are you looking for hard facts only in the present day?
Dr. Lauriane Chalmin-Pui
Really interesting question. So I think that at the end of the day, we are all the same species with Animals, you know, we have our habitat our habitat is increasingly for, for most people in the world, urban. And I don't personally, I kind of understand the very big dichotomy between urban manmade environments and nature when especially these are often contrasted.
But I think that what's important and what we as a as a kind of modern day human need is, is the balance and the integration of those two things. I think that often there can be a very easy over attribution to these evolutionary arguments, that we are a much more today we are much more mediated by our cultural experiences, whether that is nationality or race or gender, or just just past experiences that we've had as individuals. And I think that for most people, that will probably be the more important when we think about emotional reactions that often will kind of override any evolutionary aspects.
But I think that we certainly at the basic level, yes, we are, we are drawn to nature. But the question is, which kind of nature and and the you know, a tree is something that is very understandably, nature, a virus or pathogen less so. So I think, you know, sometimes we've got to, we've got to really understand what we're talking about. And sometimes it can be over generalized. So. Yeah, I mean, I think there is definitely an importance for that, for that science of understanding what it is, and what reactions are we finding? And the, the argument isn't, it doesn't always just go back to, you know, where did we evolve?
Matt Morley
It think that's critical. It's, it's too much of a, of a, an umbrella concept to just say, well, nature dominates nurture. So it's not about what we've learned, but it's about what we were born with in our DNA, and therefore, Biophilia is, is already proven, and we don't need to back it up. I think it's, we need, we need both, we need an understanding of the science that's proving that it's still present today. And that we are in fact, reacting as perhaps an evolutionary approach might suggest, we need to
Dr. Lauriane Chalmin-Pui
definitely and I think we also need to understand our impact on nature. So things like sustainable practices, environmental, Pro Environmental behavior, things like that. I mean, they may sound quite small in the grand scheme of things, when you look at, you know, the huge tipping points of climate change and things like that. But ultimately, that integration, however much nature there is in your environment, you still depending on the water, you're still depending on the air, you're still depending on climate stability.
And we do need to understand our impacts on that and how it all ties in. And I think that's how just to go full circle back to the kind of Environmental Horticulture it's not. It's not just our well being versus a planetary natural, you know, very Green Planets everywhere. It's really about everything coming together and everything is interlinked and equally important.
Matt Morley
I think we should close on that. That's a big thought to wrap things up with thank you so much. Well, we'll leave a note. We'll leave a mention of the well being garden book by your colleague at the IHS, Professor Griffiths in the show notes, in terms of people connecting, showing support for the RHS, how can they follow along with the work that you're doing that?
Dr. Lauriane Chalmin-Pui
Well, we've got a oh, I can't remember the URL, you might have to link it. But we've got some we've got plenty of pages on our website that has links to all of this well being research. People, of course can contact me directly if there is a specific question or access to a specific paper or study in terms of more generally gardening inspiration for for example, small spaces, things like that.
The rest of the RHS website https://www.rhs.org.uk/ also has plenty of horticultural knowledge that is freely available. You don't have to be in the UK but of course it is probably more biased towards UK plants. And in terms of sustainable gardening practices, again, there's a wealth of tips and advice on the RHS website.
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