How does your garden grow?
In recent years, Wilmot Gardens at the University of Florida sat in disrepair — until Craig Tisher, M.D., former dean of the UF College of Medicine, started eyeing the space. Now, Wilmot Gardens is not only a preserved green space on campus, it also hosts a horticultural therapy program where patients meet in therapy groups and the science of horticultural therapy is conducted.
By: Morgan Sherburne
Elizabeth “Leah” R. M. Diehl holds up a potted plant in front of the class.
The plant is a little scraggly, and a lighter shade of green than its counterparts on the table. Its mostly bare branches shoot out over the side of its pot.
“We just want to give this one a full haircut,” Diehl says.
Diehl, R.L.A., H.T.M., director of the therapeutic horticulture program at The Greenhouse at Wilmot Gardens on the University of Florida’s campus, is giving the group a lesson on how to start a cutting from a plant.
All of this group’s attendees have either suffered a stroke, have Parkinson’s disease or are the caregiver of a person with a movement disorders affliction. Some attendees use canes. Another is in a wheelchair. But they’re all in the greenhouse for the same reason: a weekly therapeutic horticulture session.
This week, the attendees are working with a fuzzy-leafed plant called the false African violet. Diehl watches an attendee snip a cutting from a plant.
“Tom, that looks perfect,” she says.
Tom Mitchell, of Alachua County, has Parkinson’s disease. Since his diagnosis, he and his wife, Pat, have thrown themselves into art, tai chi and dancing classes offered through the UF Health Arts in Medicine program.
The therapeutic horticulture group is the Mitchells’ most recent endeavor.
“It makes for a comfortable atmosphere — and not all atmospheres are comfortable when you have Parkinson’s,” says Pat Mitchell. “It’s really calm in here. It’s just a very happy, peaceful building.”
Preserving a green space
In 2006, Craig Tisher, M.D., then the dean of the UF College of Medicine, began thinking about Wilmot Gardens. The gardens were named for Royal James “Roy” Wilmot, a horticulturist with the Florida Agricultural Experiment Station who, with others, founded the American Camellia Society at UF and served as its first secretary and yearbook editor. Upon his death in 1950, colleagues and friends from around the world donated more than 300 camellias to the gardens in Wilmot’s honor.
When Tisher turned his attention to the gardens, the chunk of land was almost completely consumed by vines, overgrown trees and palmettos and the university was eying it for a building. But instead of brambles or a construction site, Tisher saw a useful space.
Its usefulness was partly practical. The UF Health campus would eventually expand, and, bound by University Avenue to the north, Archer Road to the south and 13th Street to the east, the campus could only grow westward.
“The gardens themselves were eventually going to end up being in the middle of the Health Science Center campus,” Tisher says. “And I thought it was important that we preserve that space, and preserve it as a green space.”
Looking for funding to support the garden’s restoration, Tisher assembled a team to apply for a grant through the TKF Foundation, a nonprofit that funds the creation of green spaces in urban areas. The grant included a requirement: that the green space has some sort of positive effect on a target population.
“We realized that, in our group, we had a registered horticultural therapist — and that was Leah Diehl,” Tisher says. “We were so taken by the idea that we said, ‘Even if we don’t get this grant, we’ll set a therapeutic horticulture program up on our campus.’”
Although the group was a finalist for the grant, they did not receive funding. Diehl began running the horticultural therapy program in space borrowed from the greenhouses owned by the UF department of environmental horticulture while the Wilmot Gardens greenhouse was under construction.
Designing a program
When Leah Diehl’s brother was just 2 years old, he suffered a brain trauma that left him developmentally disabled for life.
As they grew up together, Diehl watched her little brother go through their state’s special education system. On the cusp of her college career, Diehl had to make a difficult decision: to start studying architecture, or to focus in special education.
“I finally decided I would go to architecture school,” Diehl says. “I figured I could volunteer in special education, but I could never volunteer in architecture.”
Diehl oversees several horticultural therapy groups, including a stroke group supported by a grant through the Christopher and Dana Reeve Foundation, and the movement disorders group, supported by the UF Health Center for Movement Disorders and Neurorestoration. A group of patients with cancer, supported by the Gainesville nonprofit Climb for Cancer Foundation, meets for the program as well. But Tisher and Diehl also saw opportunity to start gathering research about whether horticultural therapy has measurable effects on people with different kinds of illness.
To that end, the program received a grant from the Paralyzed Veterans of America to work with veterans with spinal cord injuries. A 2013 grant from the nonprofit Dialysis Clinic Inc. supported a study to see how horticultural therapy affected patients who had chronic kidney failure and who were on dialysis.
Diehl says she can see changes in the people who come for their therapy sessions.
“We’ve had many people in the program who start out very quiet, with very little expression on their faces. After a couple sessions, they start to smile,” Diehl says. “I could fill your day with anecdotal evidence of improvements in people. But it’s so important to be able to put numbers to these improvements as well.”
Analyzing the greenhouse
Regina Bussing, M.D., a psychiatrist and interim chair of the UF College of Medicine’s department of psychiatry, worked with Tisher, study coordinator Dana Marie Mason and UF psychiatrist Tessy Korah, M.D., to develop a study for patients who are admitted to the UF Health Shands Psychiatric Hospital’s inpatient unit.
Bussing and Margaret Hannon, a recreational therapist, ran a pilot project to assess whether a longer study could be completed. The initial group of patients who went to the horticulture therapy program seemed to find it helpful.
“The reason we did the study is because we got so much positive feedback from that pilot group,” says Dana Mason, study coordinator for the department of psychiatry.
With the pilot project a success, Bussing and her fellow researchers began recruiting patients with severe depression who were either inpatients or had been recently hospitalized at UF Health. To determine how the program affects patients, researchers compare study participants using standardized psychometric health outcomes surveys with a control group of patients who are following a more typical regimen of care, Mason says.
Although the final analysis of the data is not yet complete, Bussing says patients feel they enjoy the experience — results that she sees across scientific literature examining benefits people find from the natural environment.
Bussing points to a study completed in Utah that surveyed 5,000 people. The survey included a few questions about gardening — and found that people who actively gardened had fewer symptoms of depression than those who had never gardened.
“Generally speaking, you find improvements in attention span and ability to think clearly, as well as physical improvements in blood pressure regulation, and decrease of stress or burnout or anger,” Bussing says. “For us, it was also a natural extension to look
at depression responses.”
Sprouting the science of therapeutic horticulture
By Jack Payne
We all sense it: Gardening makes you feel better.
If we can establish that science, not just sensibility, underlies the positive effect of gardening programs such as therapeutic horticulture on participants, it might someday lead to their coverage by health insurance just like drugs, counseling sessions and physical therapy.
We may be some distance from turning gardening into medicine. It’s the kind of audacious challenge that a certain type of university is best equipped to take on — namely, one with both medical and agricultural branches on the same campus. The University of Florida is one of the few.
That puts us in a position to be a leader in horticultural therapy. It takes a leader to help us fulfill the potential of UF Health and the Institute of Food and Agricultural Sciences working together.
Craig Tisher, M.D., who was dean of the College of Medicine from 2002 to 2007, has built a bridge connecting IFAS plant experts with behavioral and cognitive psychologists and neuroscientists at the Evelyn F. and William L. McKnight Brain Institute of the University of Florida.
That wasn’t Tisher’s goal when he set out a decade ago to take a neglected patch of greenery off Gale Lemerand Drive and turn it into a spectacular oasis that we know as Wilmot Gardens.
Tisher’s initial aim was to restore the Wilmot Gardens, best known in the past as a camellia and azalea garden, to its original beauty to be enjoyed by patients and their families, faculty, students and staff.
Largely through the support of dedicated volunteers, many who worked every other Saturday morning for more than eight years, and the receipt of funding from a host of generous philanthropists, Wilmot Gardens is becoming not just a refuge, but a patient care, teaching and research center.
For example, the UF College of Medicine now employs Leah Diehl, a horticultural therapist, as director of therapeutic horticulture. The garden is becoming the hub for graduate research in horticultural therapy.
So the bridge that Tisher built has made the University of Florida a leader in defining a role for horticultural therapy in delivering care to patients.
Through his work in recruiting campuswide assistance for the Wilmot Gardens restoration, Tisher found Charlie Guy, Ph.D., of the UF/IFAS environmental horticulture department. Their partnership led to the current research to measure the effects that gardening activities such as seed planting, transplanting and caring for plants have on participants’ mental health.
In this research, subjects respond to questionnaires on how the activities affect their well-being and quality of life. The real groundbreaking work is Guy’s partnership with UF medical researchers at the McKnight Brain Institute, where the participants undergo functional MRIs to observe the response of the brain when people work with plants. UF is the only place we know of doing this innovative work.
The UF Health-IFAS connection has the potential to go far beyond the current research. For example, Guy has submitted a grant application to NASA to investigate whether the psychological benefits of gardening can help astronauts be more effective in their space missions.
On Earth, the work of Tisher, Diehl and Guy and their colleagues could lead the way toward a scientific basis for having people care for plants as a way of caring for themselves.
Some people even tell Tisher that his post-retirement work on Wilmot Gardens may well be his most visible and lasting legacy. In any case, his work with IFAS is an example of his continued commitment to patient care and research years after he left the dean’s office.
Jack Payne is the University of Florida’s senior vice president for agriculture and natural resources and leader of the Institute of Food and Agricultural Sciences.
Connecting the dots
Researchers are looking not only at the benefits for people who are ill, but also at how therapeutic horticulture affects people who are healthy. Charles Guy, Ph.D., a professor of plant physiology and biochemistry at the UF Institute of Food and Agricultural Sciences environmental horticulture department, first became involved when Tisher reached out to Guy’s department to help establish a research arm in the program and to create temporary space in the environmental horticulture department’s greenhouses.
At the same time, an undergraduate, Christine Penman, had been volunteering for Diehl since the beginning of the horticultural therapy program, and was interested in further study of the field for her master’s degree. She worked with Guy, Diehl and Tisher to create a research project that would advance the science of horticultural therapy.
“There’s a huge body of mostly anecdotal literature saying that people who are engaged in gardening are less stressed, happier, healthier and more friendly,” Guy says. “But the science, the empirical evidence, hasn’t been quantified very well.”
To formulate a study that would help lay that foundational science, Penman and Guy met with Sara Jo Nixon, Ph.D., a professor of psychiatry and psychology in the College of Medicine; Song Lai, Ph.D., director of the UF Clinical and Translational Science Institute Human Imaging Core; and Natalie Ebner, Ph.D., an assistant professor of psychology, who furnished Penman and Guy with knowledge about behavior, psychology, neuroscience and brain activation.
The group helped Penman and Guy design a study that would try to connect three dots: The first dot was having people work with plants, Guy says. The second dot was to determine the therapeutic benefits of that work. The third dot — the hardest dot to connect — would be to see what effects those first two dots might have on brain function, using functional magnetic resonance imaging, or fMRI, to measure the change. When Nixon suggested measuring the possible effect using fMRI, Guy’s interest was further piqued.
“My entire career has been about measuring things quantitatively, so when you talk about measuring brain activity, I was all for it,” Guy says. “If we could connect those three dots, then we’ve made an important contribution to the scientific field.”
The two gathered 23 healthy women, 12 of whom were in the treatment group and 11 of whom were in a control group that did not participate in gardening. Over a period of six weeks, the gardening group participated in 12 hourlong sessions. At the beginning and end of the study, the groups took surveys to assess mood, stress, depression and anxiety. The researchers found that many of the participants started the study with high anxiety, high stress and significant depression, even though they were screened for wellness.
“By the end of the six-week program, we saw a drastic reduction in their reported stress and depression,” Penman says. “It made us think there was something going on here, that you would see such drastic results in a healthy population.”
To see how their experience might affect brain function, the women also received fMRI scans before and after the gardening treatment. During the scans, the women viewed photos of plants and women interacting with plants. Penman was trying to see whether different areas in the brain were activated when the participants were reminded of their time in the greenhouse.
Penman and Guy are still assessing these results, but they hope their study will be a starting point for other similar studies.
“When we started this project, we had no idea of where to look in the brain or how to assess how the general public may be affected by interacting with plants,” Penman says. “I think this really was a pilot study that now can be taken in hundreds of different directions.”
The next calling
With the Wilmot Gardens greenhouse completed in 2014, the therapeutic horticulture program and the gardens continue to grow. Tisher and his fellow volunteers are planning a healing garden. The Gainesville Bromeliad Society planted a garden of bromeliads — the family of plants that ranges from pineapples to Spanish moss. Thirty rare Japanese maples recently gifted to the gardens are now growing their spiky leaves in another corner of the gardens.
“I wasn’t sure what I was going to do after I stepped down as dean,” said Tisher, who for a while held the title of vice president for program development. “I had a lot of interests, but one can only play so much tennis or restore antique tractors for so long.
“I enjoyed working to try to bring back Wilmot Gardens to its previous beauty, and I thought maybe that’s my next calling — to work in this program.”
So what’s the payoff for Tom Mitchell, the Alachua County resident with Parkinson’s disease? The class gives him a good excuse to be outdoors. He likes working with his hands — something he did during his career as a medical physicist in radiation oncology at what is now the Davis Cancer Pavilion
at UF Health. He retired in 2007.
“I’ve never been a gardener. My gardening experience was limited to mowing the grass,” he says. “Now, I’m getting into bamboo.”
Mitchell makes walking canes and wind chimes from the Buddha’s belly bamboo and the stem-stripe bamboo he has started to grow on his 10-acre property, also full of oaks
“We salvaged wood from a big oak tree that blew down and planted staghorn ferns in the tree stump. We learned to do that here,” Tom Mitchell says. “When you live where I live, you have
to be self-reliant. And it’s not only fun, it’s essential.”