New Blog Writers Introduced
HTI would like to introduce and welcome it’s two new blog writers, Colleen Griffin, HTR, from Maine who will be writing on a variety of topics with a focus on the US. Her co-writer will be Daniela Silva-Rodriguez Bonazzi, from Peru, who will cover international HT. This month begins with Colleen’s take on some of the research in horticultural therapy.
Colleen Griffin, HTR

As a registered horticultural therapist practicing in Southern Maine, I am continuously awe-struck by the ability of HT to promote pride in oneself and foster a sense of well-being in so many. Currently, I have the good fortune to work with special needs students, grades K-8, in a passive solar greenhouse. In addition, I work with adults and children whose lives have been touched by cancer at Dempsey Center, a cancer care foundation. At Dempsey Center, my work is focused on expanding their community gardens, conducting HT sessions within the garden space and contributing to the development of a survivorship program. I look forward to the challenge of co-writing the HTI blog.
“Horticultural Therapy…What’s that?”
How do you answer this question?
By Colleen Griffin, HTR

When you encounter someone who is unfamiliar with horticultural therapy, and I am sure you have, how do you explain what the profession involves? My response to the question, is usually, “It is the practice of using plants and gardening activities as a therapeutic tool”. This response leaves me feeling a bit flat, as though I have shortchanged what my profession embodies. I struggle with how to sufficiently, yet briefly, define what horticultural therapy is and more importantly, the benefits of the practice. I found that the best explanation resides within the people-plant relationship.
We are aware of the people-plant relationship being central to the practice of horticultural therapy. It is common knowledge that humans exist today because plants provide the essential tools for our survival. Therefore, it makes sense that when humans are looking to reduce the influence of stress in our lives, we would turn toward nature. But in this age of technology, many have forgotten this valuable connection. Far too often, we see harmful effects from the very practices that strive to improve quality of life because this primal relationship is disregarded.
As I searched to gain a deeper understanding of the value of the people-plant relationship, I examined the human response with nature from a physiological perspective. The following three research studies make clear the physiological as well as the psychological benefits of this vital alliance.

“Place can make you sick… and place can make you well”. Dr. Esther Sternberg, M.D. is a Professor of Medicine and Founding Research Director for the Arizona Center for Integrative Medicine at the University of Arizona. Dr. Sternberg believes there is a complicated yet intimate relationship between our five senses, our emotions and our immune system. Simply put, when we stimulate our sense of smell, touch, taste, sight and hearing in a positive manner our emotional state is elevated. When our emotional state is elevated our stress level lowers. By maintaining a lower stress level, our immune system is less burdened. It is obvious to all that spending time in the garden will stimulate all five senses in a positive manner, lower your stress level and therefore will bolster your immune system. Dr. Sternberg maintains that our environment is of critical importance to our overall health and wellness. She goes on to declare that “the science of place and well-being is today, the cutting edge of medicine”.

Attention Restoration Theory or ART was developed by Stephen and Rachel Kaplan, Environmental Psychology professors at University of Michigan. They claim that humans are capable of only two types of attention, directed and involuntary. Directed attention requires concentration and causes mental fatigue. It is part of your fight or flight response. You use directed attention while learning a new skill, multi-tasking or conversing with others. Involuntary attention does not require effort and is restorative. It is part of your rest and digest response. You use involuntary attention to recover from the fatigue produced by directed attention. Involuntary attention occurs readily in a natural environment. Think of attending a conference, being enclosed in a dark room, staring at a bright screen with flashing images. Your brain is overloaded with new information. During your lunch break you step outside. It is a warm, sunny day, flowers are blooming, birds are singing…. your attention immediately switches from directed to involuntary. Your stress level drops, you breathe deeper and your mind clears.
An inherent benefit of involuntary attention is the production of T-lymphocytes, aka natural killer cells. T-lymphocytes are white blood cells produced in the thymus gland that fight inflammation throughout the body and are an integral part of your immune response. This coincides with what Dr. Sternberg claims, that being in the presence of nature is beneficial to our immune system.
View Through a Window May Influence Recovery from Surgery This landmark study conducted by Roger Ulrich, Ph.D., further supports the validity of the people-plant relationship. Ulrich’s study uses surgical records of cholecystectomy patients in a suburban Pennsylvania hospital over a nine-year period. Twenty-three patients were assigned to a room that overlooked a natural environment with trees and wildlife. An additional twenty-three patients were assigned to a room on the other side of the post-operative ward that had a view of a featureless brick wall. The patients with a natural view required less pain medication, had a shorter hospital stay and generally reported a more positive post-operative experience than their counterparts on the other side of the ward. The evidence is clear, being in the presence of nature helps to speed recovery. Since the publication of this research in 1984, it has been recreated countless times from North America to Asia and from Northern Europe to Australia, always achieving the same result. A most compelling fact, one which cannot be ignored, is this body of research does not take into consideration the socio-economic status, cultural differences or even gender of the research subjects, yet the results do not waiver. Humans are not independent, but most certainly a part of the natural world.

Having a deeper understanding of the people-plant relationship has afforded me more confidence as I describe my chosen profession and the indisputable benefits of the practice. When I focus on what is happening on a physiological level during a sensory experience it becomes clear. Being in the presence of nature leads to the stimulation of your five senses, involuntary attention takes over, your blood pressure drops, you breathe deeper and slower, and you experience clarity of mind. These changes contribute to a happier emotional state, your stress level drops which in turn helps to protect your immune system.
In my experience, the profession of horticultural therapy is largely misunderstood and at times marginalized. The need to educate those around me is a very important element of my HT practice, one that can be frustrating and at times exhausting. But as I crouch in the garden, beside a six-year old with developmental disabilities as he harvests his first radish, the look of wonder and pride I see in his eyes once again confirms that I have chosen the right path.
References
Sternberg, E. 2009. Healing Spaces: The Science of Place and Well-Being.
Cambridge, Massachusetts: Harvard University Press.
Ulrich, R. S. (1984). View Through a Window May Influence Recovery from Surgery. Science
(New York, N.Y.). 224. 420-1. 10.1126/science.6143402