"It is a drug:" The impact of gardening on the mind

6/21/2017

You’ve heard it all before: Gardening is great exercise.

It encourages you to eat healthy and use your back, biceps, shoulders, thighs, glutes, and hamstrings. Whether you’re digging dirt, planting seeds, or moving a loaded wheelbarrow around the yard, you do a lot of squats and lifting — and your muscles get a slow workout burn that rivals what a lot of people spend good money to get at a fancy gym.

According to one study involving more than 4,000 people ages 60 and older, adults who garden regularly or engage in other forms of home improvement can reduce risk factors for heart attacks and strokes as much as 30 percent. The U.S. Centers for Disease Control and Prevention claims 2.5 hours of gardening a week can reduce risks for other problems, too, including obesity, colon cancer, Type 2 diabetes, osteoporosis, and premature death.

And a major Australian study that evolved over 16 years — one that involved 2,800 people over age 60 — showed the risk of getting certain types of dementia can be reduced 36 percent by people who garden regularly, because of how it helps them maintain their cognitive function.

But there is precious little that gets to the inherent root of why we do it.

What is it about the human psyche that drives so many of us to plant seeds and grow our own crops in the first place?

Researchers believe it goes well beyond the sense of accomplishment successful growers get at harvest time — when the end result is tasty, homegrown fruits and vegetables — and probably involves a sensation to a part of our brain that gives us pleasure when we reconnect with nature.

Though there is limited research into the actual physiology, regular gardening is an exercise that seems to give a sense of euphoria comparable to what long-distance runners get from their “runner’s high” when their brains release endorphins, according to MaryCarol Hunter, an associate professor in the University of Michigan’s School of Natural Resources & Environment.

“It is a drug,” Ms. Hunter said, brushing off a suggestion that it’s not. “It is a drug. Gardening is exactly in the same realm as interacting with nature. It can produce an effect that is like a drug.”

An expert in environmental psychology, Ms. Hunter said there isn’t much published research on the positive feelings that gardening creates, and nothing, from what she can tell, on why some people don’t like to garden.

But she agrees it’s a fascinating topic, a wide-open field of research.

Think about it. Though some people think of gardening as a pain in the rump, others get goosebumps from that earthy feeling of sticking their hands in warm, moist soil. Some view the act of gardening as almost a religious experience, an outdoor activity that makes them feel more connected to God.

Exercise in general releases neurotransmitters that make us feel good, such as serotonin and dopamine, while lowering cortisol, a hormone associated with stress. It also helps us sleep better.

Ms. Hunter has come full circle on gardening, reaping joy from what she once considered an annoying chore.

As a child growing up in Detroit, gardening was a pain to her. She grew tired of being out in the hot sun, pulling weeds as one of her chores. But things changed as her mother wisely devoted a small plot of land in their backyard to her as her own, encouraging her to buy her own seeds and grow her own plants.

That sense of ownership “was the thing that adjusted my attitude that this was a good thing to do,” Ms. Hunter said.

One of the pioneering studies into the psychology of gardening came in 1973 from one of Ms. Hunter’s colleagues, Rachel Kaplan, a retired University of Michigan professor of environment and behavior, natural resources, psychology.

In it, Ms. Kaplan found women especially found gardening uplifting back then because it is served as an escape from their duties as housewives while connecting them to nature in their own backyards.

“In the absence of waterfalls and beaches nearby, the garden may be particularly satisfying to those most content in the natural environment,” Ms. Kaplan wrote in her 16-page paper. “It is in retrospect hardly surprising that gardening emerges as a powerful source of fascination. It appears to possess a great many properties that would tend to enhance fascination.”

The garden, according to Ms. Kaplan’s research, is “a slice of nature compressed in space and a pattern of information compressed in time.”

“Rarely is so broad a spectrum of nature and natural processes found in so little area,” she wrote.

In more recent years, studies have emerged from across the world to help build upon the global baseline of information.

A 2011 research project in the Netherlands showed stress-inducing cortisol levels went down among 30 people randomly assigned to either 30 minutes of outdoor gardening or indoor reading. But those who performed gardening achieved much better results. The authors said their findings show gardening “can promote relief from acute stress.”

In a 2016 paper, environmental experts from Japan and the United Kingdom claimed to have found “robust evidence for the positive effects of gardening on health” by examining cross-discipline research into physical, psychological, and social health.

“A regular dose of gardening can improve public health,” their report stated.

Researchers at the University of Copenhagen in Denmark have looked into potential benefits of a “healing garden” on patients with chronic stress. The BBC has reported on a garden project in London being used as therapy for patients with schizophrenia and other mental health issues.

Many research projects in the United States and other parts of the world have focused on community gardens, which offer a different dynamic than those planted by individual backyard warriors.

With community gardens, there’s the opportunity for teamwork. There can be less anxiety, too, when people who aren’t master gardeners are allowed to gradually pick up tips from those with more experience, Ms. Hunter said.

“For a lot of people, doing it at home isn’t the best option,” she said. “A lot of people like to be social. Community gardens are where everyone pitches in.”

Community gardens promote “a feeling of social cohesion with other human beings,” Ms. Hunter said.

“This need for making connections with people other than family members is enormous,” she said. “There’s a lot of problem-solving in a garden.”

A 2008 Australian study said community gardening “offers many health and well-being benefits.”

“The garden was felt by members to be a sanctuary where people could come together and escape daily pressures, a source of advice and social support, and a place which gave them a sense of worth an involvement,” the study said.

Members saw their community garden as a way of giving them a connection to nature and promoting spirituality in their life, the report said.

A 2015 study headed by the Colorado School of Public Health found that community gardening appears to “stimulate a range of interpersonal and social responses that are supportive of positive ratings of health.”

You apparently don’t need to be pulling weeds eight hours a day under the hot, beating July sun to get at least a little benefit from gardening.

Studies show people who merely sit outdoors 15 minutes a day are likely less stressed out than those who don’t. With the popularity of community gardens on the rise, downtrodden neighborhoods in urban areas become more livable to everyone when they’re beautified by community gardens, Ms. Hunter said.

“Gardening is just another form of nature,” she added.

Contact Tom Henry at: thenry@theblade.com, 419-724-6079, or via Twitter @ecowriterohio.