Dr Sue Stuart-Smith is a psychiatrist, psychotherapist, gardener and literature lover who, in her much hailed UK bestseller The Well Gardened Mind brings all her passions together to look at the relationship between gardening and mental health.
Stuart-Smith’s book ranges widely, from bringing green spaces into housing developments, to gardens in prisons, and their use in people’s recovery from trauma.
She studied English Literature at the University of Cambridge before qualifying as a doctor and working in the UK National Health Service for many years. She is married to celebrated garden designer Tom Stuart-Smith, and over the last 30 years the couple have created the world-renowned Barn Garden in Hertfordshire.
Stuart-Smith agrees that early on she saw gardening as outdoor housework, but when she met her husband he was "a passionate and knowledgeable gardener".
They had the chance to live in a converted barn in Hertfordshire and create a garden from scratch.
"I was determined to be part of it and to try and learn but I did see it as outdoor housework for probably four or five years.
"It wasn't until I started my own little herb garden within our plot that I began to get hooked."
She grew up with the story of her grandfather, Ted, who had some horrific experiences during World War I. He was captured at sea and from the spring of 1915 spent time in a series of brutal labour camps.
He was lucky to make it home - 70 percent of the prisoners who included Kiwis and Australians died.
When he got home he was malnourished and had to be nursed back to health by her grandmother and he then enrolled in a 12-month horticulture rehabilitation course.
"And that turned his life around."
Stuart-Smith says on both sides of the lines (the German and the Allied sides) in WWI soldiers used seeds sent from home to create small gardens, usually behind the back wall of the trenches.
"What they wanted was colour - flowers that were familiar from home. I think it helped them hold on to an authentic reality, gave them a bit of beauty.
"They were after all facing the most horrendous industrialised form of warfare that had really never been seen before and a terrible blasted landscape around them."
She says it's clear from letters soldiers wrote home that these small acts of restitution helped them keep their sanity.
Stuart-Smith says the soldiers were facing long periods of inactivity between outbursts of shelling so making and tending gardens gave them something creative and constructive to focus on.
The power of having a constructive outlet is often underestimated, she says.
"And that's something that's very important for anybody recovering from trauma... you can bring something new into the world, and if you can begin to do that you can begin to imagine a different future."
She likens planting a bulb to "setting a little time-bomb of hope in motion" and says gardening has been crucial for providing a sense of future in the pandemic.
While people's plans for work or family occasions were disrupted, gardening was one activity that could safely continue.
Gardeners could start to plan two or three months ahead which is important and is connected in terms of our neuro-chemistry with the dopamine system.
"Once you start thinking about the future then other things follow like a sense of purpose, a sense of motivation and so on."
Stuart-Smith has visited the greenhouse programme on Rikers Island, New York's main jail complex.
Alongside a gardening project for inmates there is another one for former prisoners.
"It was a real privilege to visit that project and talk to the prisoners taking part in the gardening there and I was really struck during those conversation by the simple power of gardening."
She says many of the men and women have always been in trouble in various ways, haven't achieved much in their lives and never been praised but wanted to turn themselves around.
When they grow flowers and vegetables they see something they can share with others and they are praised and this boosts their self-esteem.
"It's a very very effective intervention."
In her book she describes the Incredible Edible Project that started in the north of England after the global financial crash in 2008. It has transformed the rundown mill town of Todmore, she says.
A group of women began sowing runner beans and other vegetables on a neglected site and put up a sign saying 'Help yourself'.
More empty land was taken over and now anyone, residents or visitors, can help themselves to the produce.
"It's proved transformational, it has led to gardening projects in schools, boosted the creation of allotments there and actually boosted the local economy because it's become something more of a food destination, shops have sprung up and so on.
"And it's a really flexible model."
She says one brilliant initiative in Todmore during the pandemic was the addition of book shelves in the gardening spaces, and people could take or leave books, especially children's books.
For those unable to garden, research has shown that even caring for an indoor plant can make an enormous difference to levels of mental anxiety, she says.