Flower Power

Flower Power
Finding ways to make flowers thrive
CFAES professor Michelle Jones studies bacteria that help flowering plants flourish after leaving the greenhouse.
CFAES professor Michelle Jones studies bacteria that help flowering plants flourish after leaving the greenhouse.

Story by Alayna DeMartini, Photos by Ken Chamberlain

As someone who researches flowers, Michelle Jones often hears she has the ideal job.

How else could you characterize it? Even in winter, brightly colored flowers grow all around her—in her greenhouses, in her office, and in “growth chambers” each about the size of a master bedroom closet, but packed with tray after tray of blooms.

This summer, the horticulture and crop science professor is studying extending the vase life of cut, pink zinnias. She’s also taking purple petunias, partially silencing a gene that causes them to turn purple, and producing purple-and-white-striped petunias. Inside a greenhouse, stretched across benches, are red and blue petunias, each growing in peat moss and treated with beneficial bacteria to see how well the bacteria help the flowering plants fend off disease.

What intrigues Jones about flowers is that there are hundreds of different species, hundreds of varieties, and each responds differently to how it’s grown and handled after leaving the greenhouse.

Yes, she tells people that she loves what she does, but sometimes it can be tough. Flowers aren’t food, so federal funding for research can be hard to come by. Still, flowers provide a different type of sustenance. Bright and sweet-smelling, they hold psychological value, offering a boost to people’s moods and to the paychecks of growers. Flowers are a big industry in Ohio, ranked fifth in the nation for flower production.

But flowers don’t last forever, which is exactly why Jones studied how to slow the aging process in cut carnations beginning when she was an undergraduate student in agricultural biochemistry. Through her research, she showed that before a flower dies and sheds its petals, the plant recycles nutrients from the dying petals, moving the nutrients to other parts of the plant. For about two decades, Jones studied the genes involved in keeping plants alive, and how to manipulate those genes to extend the lives of flowers.

Jones, a professor of horticulture and crop science, spends part of her time inside “growth chambers” on the Wooster campus.

Then, six years ago, she switched her focus.  

“I call it my scientific midlife crisis,” said Jones, who serves as the D.C. Kiplinger Floriculture Endowed Chair at The Ohio State University College of Food, Agricultural, and Environmental Sciences (CFAES). The position funds tuition and stipends for doctoral students interested in greenhouse flower production.

With a hankering to study something different, Jones began working with CFAES colleagues who were testing the effectiveness of bacteria that are beneficial to plants. Immediately, she was intrigued. The research is timely, considering the shift toward using fewer chemicals, pesticides, and fertilizers on plants grown in greenhouses.

Bacteria beneficial to a plant’s growth have been used for many years. But in the past decade, greenhouse growers have become increasingly interested in so-called biostimulants, natural alternatives to chemical fertilizers or pesticides that can include not just beneficial bacteria but other compounds as well. Much of the beneficial bacteria on the market for plants are for those grown outdoors, mostly field crops. 

Bacteria that spur growth

Acting similar to kefir, kombucha, or probiotic supplements for people, beneficial bacteria for plants have been shown to improve the plants’ immune systems as well as their abilities to take in nutrients and water, fight off diseases, and make nutrients more available for use.

“Years back, the thinking was that the greenhouse was a sterile, controlled system. But there are all these natural components that can be put back into the system so the plant is healthier.”Michelle Jones

“Years back, the thinking was that the greenhouse was a sterile, controlled system,” Jones said. “But there are all these natural components that can be put back into the system so the plant is healthier.”

A healthy plant will require less fertilizer and pesticides. That saves growers money, while reducing the risk of pests developing a resistance to chemical pesticides. Plus, butterflies and other pollinators benefit from safer pollen. 

Jones tests which bacteria can best help plants thrive under stress—specifically, under the conditions in some retail stores where water, light, and temperature might not be ideal. In stores, plants likely receive no fertilizer and might not be watered frequently. After coming from a greenhouse where all of those conditions were closely controlled, the retail environment can be a shock. So, the quality of plants arriving at stores typically is high, but sometimes fades quickly. 

Applied as a liquid, beneficial bacteria can be provided weekly as part of the mixture given to the plants that grow in peat moss and bark under the natural and artificial lights of a greenhouse.

The ideal outcome is more resilient plants that last longer and require about 25% less fertilizer, thus saving growers money and reducing the risk of fertilizer runoff.

“We’re seeing some really exciting results from these studies,” she said. “We’ve grown petunias, impatiens, and pansies using less fertilizer and treating them with beneficial bacteria. They end up with higher nutrients in the leaves, despite getting less fertilizer.”

Jones is studying extending the vase life of cut zinnias.

Jones and her colleagues are working with Pseudomonas, a type of beneficial bacteria found along the roots and other surfaces of plants as well as inside plant tissue. The bacteria have been shown to make soybeans and other crops more resilient to diseases.

Whether those same bacteria can also bolster the growth of greenhouse-grown flowers is what Jones and others are trying to determine. Among flowering plants, what works for one variety might not work for another. Considering there are hundreds of species and varieties of flowers, the research on finding beneficial bacteria effective for them can be challenging.

“What we’re trying to do is make sure the beneficial bacteria colonize and have their full potential in the greenhouse,” Jones said.

So far, Jones and her colleagues have found some bacteria from the collection of Pseudomonas that will enhance the growth of flowers. The bacteria lead to more and larger flowers.

They’ve also tested some bacteria that can help a plant fend off one of the most common diseases in greenhouse-grown plants, Botrytis cinerea. The fungus that produces gray mold, or botrytis, on plants and can kill them has developed resistance to many of the chemical pesticides used to fight it.

“A lot of these (Pseudomonas) bacteria show promise for reducing the severity of the disease.”Michelle Jones

“There’s a lot of interest in natural options to fight off the disease,” Jones said. “And a lot of these (Pseudomonas) bacteria show promise for reducing the severity of the disease.”

Experiments with the Pseudomonas bacteria reducing the severity of botrytis are wrapping up, with the next step being working with companies to create products that can be sold to greenhouses.

Loving science first, then flowers

Though her work now surrounds her with flowers, Jones, 48, didn’t grow up with a fervor for flowers or plants. She didn’t garden as a child. Her parents didn’t garden. But she grew up in Iowa, so farms were all around her, and early on, science enthralled her.

Her grandfather was a professor of forest products at Iowa State University.

“He was always trying to teach me all the names of the different trees. I could never remember them all.”

As a sophomore in high school, she first competed in science fairs at the local, state, and national levels. Each year, after all the competitions were over, she didn’t box up her project and hanker to try something totally different the next year. Instead, each year’s project built on the previous year’s. So there was a Phase 1, 2, and 3 to her high school science project on the effects of fertilizer runoff—likely an early sign she had the stamina and focus to research a single subject for years.

Jones has linked a flower’s shelf-life to the molecular and biochemical pathways that control how long the flower lasts.

Her first year, she started with various amounts of chemical fertilizer added to water in simulated ponds—plastic containers with plants, worms, and snails—where she tracked what grew and what died. The last year, she compared water samples she took from eight area farm ponds.

In the high school science competitions, she’d meet students from across the country, and though she told them she was from Iowa, some would say Ohio, inadvertently mixing up the Midwest states. “This is Michelle from Ohio,” they’d say. In her naturally soft voice, she’d gently correct them. “Iowa,” she’d say. She thought it was funny, having never even visited Ohio. Their gaffes turned out to be prophetic because eventually, she would move to Ohio in 2001 and accept a job with CFAES. She would indeed become Michelle from Ohio.

Jones’ attraction to science led her to major in agricultural biochemistry as an undergraduate, but she quickly found out she liked the biology side much more than the chemistry. She was far more interested in genetic engineering than, say, studying the rate at which enzymes speed up a chemical reaction.

Her research initially focused on extending the longevity of flowers. She continued with that into her first faculty position at Colorado State University at a time when Colorado had a significant industry in cut carnations.

“I may be an expert in a very small piece of this, but I see them as the experts on greenhouse production. This is their business, their livelihood.”MIchelle Jones

To the layperson, keeping cut flowers as long as possible means trimming off the stems at an angle, pouring in the packet of white powder that comes from the florist, and changing the water every few days. Jones, for her part, has studied why that does or doesn’t work, and why some flowers stay fresh for a handful of days while others last for a week or longer. She knows how to manipulate the genes that cause certain cut flowers to die in a few days while others survive for a week or more.

You might expect a professor of horticulture and crop science whose research focuses on flowers to have an elaborate flower garden of her own. When asked about it, Jones shook her head and scrunched her face. 

She has a lot of flower beds, yes, but of course a lot of weeds too.

“It’s hard to keep up with,” she said.

Focusing on her students and family

What’s striking about Jones is her understated nature, especially apparent when she talks about the role she plays when working with greenhouse growers.

“I may be an expert in a very small piece of this, but I see them as the experts on greenhouse production. This is their business, their livelihood.”

By partially silencing a gene that produces purple in petunias, Jones can test gene-functioning in the plant.

So, Jones feels privileged that people ask her for advice on how to better run their greenhouses. She likes how the industry is receptive to trying new techniques and products.

To the students whose research she oversees, Jones gives a lot of her time and nurtures their talents, said David Francis, a CFAES professor of horticulture and crop science.

Instead of being self-promoting, Jones promotes the work of the graduate students she advises, he said.

At national meetings and conferences, it’s common for faculty to present the work of graduate students they’ve supervised. Instead, Jones encourages her students to make those presentations themselves, and she helps prepare them to do so, Francis said.

“That’s a good example of her lack of ego,” Francis said.

And the students who work with Jones have reaped the benefits of that. They’ve won numerous awards through the American Society for Horticulture Science or other venues, he said.

“She works hard to put her students in a position where they can get in front of the public and present their research,” Francis said.

“She works hard to put her students in a position where they can get in front of the public and present their research.”David Francis, CFAES professor of horticulture and crop science

Kaylee South, who’s in her fourth year of a PhD program, described Jones, her faculty advisor, as nurturing. Once Jones knows the career or research interests of the students she works with, she helps them find opportunities that will help them, South said.

“She pushes us to do our best, but doesn’t want us to be completely stressed out,” South said.

And South admires that Jones seems to have a good balance between her work and time with her husband and two daughters, a 16-year-old and a 12-year-old.

While Jones’ eldest daughter is interested in animals, her youngest seems to share Jones’ fascination with plants—growing anything she can, from kiwis to avocados, all from seeds. She loves paging through garden catalogs, building a wish list. This year, she completed a science fair project on zinnias, one of the flowers her mother researches.

Jones would love to see her youngest daughter pursue a career in horticulture, or at least science. But she’s also trying to thwart that natural parental urge to push a passion onto a daughter or son. It seems she’s figured out that balance, being encouraging without pressing hard, projecting confidence, yet with a soft voice.