Research at Clark University's Experimental Plant Investigation Center is exploring new ways to enhance soil health and, in turn, improve food security.
Led by Assistant Professor of Biology Chandra Jack, the experiments inside the 1,275-square-foot greenhouse focus on how biological nitrogen fixation can reduce reliance on synthetic fertilizers. A key aspect of the project is lighting supplied by Hort Americas.
© Photos by Chandra Jack and Steven King
Jack joined Clark University in 2021 after previously researching wheat in Washington state. Before relocating to Worcester, Mass., she knew continuing her work would require something beyond a traditional laboratory.
"As part of my negotiation package, I made it clear that I needed a controlled environment greenhouse to conduct year-round research," Jack explained. "Especially here in the Northeast, natural sunlight is limited during the winter months. If you're going to rely on lighting anyway, you might as well go all out and create a fully controlled environment."
Besides shielding experiments from unpredictable outdoor variables, the greenhouse also allows for precision. By controlling every aspect of plant growth — from light intensity to soil conditions — Jack and her team can conduct research that is impossible to do outdoors.
Improving soil and crop management
The foundation for Jack's work addresses one of modern agriculture's biggest challenges: the overuse of synthetic fertilizers. While these fertilizers can boost crop yields, their long-term environmental impact is severe. They damage soil health and contribute to pollution.
Jack's research focuses on biological nitrogen fixation, a natural process in which specialized bacteria convert nitrogen from the atmosphere into a form that plants can use. The process is common in legume crops, such as beans and lentils, thanks to their symbiotic relationship with these bacteria.
However, cereal crops such as wheat and corn — which account for a significant portion of global agriculture — do not naturally engage in this symbiosis.
"My work looks at this challenge from two angles," Jack said. "First, how can we improve the symbiotic relationship in legume crops? Second, how can we create soil conditions that support free-living nitrogen-fixing bacteria for cereal crops?"
The impact of this research extends beyond individual crops. By reducing synthetic fertilizers, farmers can ultimately lower costs, improve soil health and contribute to a more sustainable agricultural system.
Finding the right lighting
A key factor enabling the success of the EPIC greenhouse is the Verjure™ Arize® Element L1000 LED greenhouse lights, provided by Hort Americas. The full-spectrum grow lights mimic natural sunlight and enable year-round research.
"Lighting is critical because it allows me to grow multiple crops with varying light requirements simultaneously," Jack added.
For example, wheat requires high-intensity light, while clover species thrive under lower light conditions. The flexibility to adjust light intensity and duration makes the L1000 an invaluable research tool.
Additionally, it helps accelerate plant growth cycles. In previous setups, certain plants took more than seven months to flower. Now, under the optimized conditions in the EPIC greenhouse, the timeframe is reduced to just three months.
Beyond improving research efficiency, the lighting system also ensures consistency across experiments.
"With consistent light sources, we can better understand how modifying variables like soil or bacteria impacts plant traits," Jack stressed. "Having that more consistent light source has been game-changing."
Future impact
Although the EPIC greenhouse is still relatively new, it is already delivering promising results. The enhanced lighting and controlled environment have allowed Jack's team to accelerate their research, providing insights into how different bacteria influence plant growth and productivity.
"One of our ongoing projects focuses on clover species and how they select bacteria that provide the best benefits," Jack said. "We're tracking how these choices impact biomass and other growth factors over time. It's fascinating to see how much variation exists depending on the bacterial strains present."
While much of the research is still in its early stages, there's strong potential for real-world impact. A big challenge is encouraging farmers to transition from synthetic fertilizers to sustainable practices. This shift often involves an initial adjustment period where costs may be higher before long-term benefits become clearer.
"Getting farmers on board requires not just research but also education and collaboration," Jack emphasized. "We're exploring partnerships with growers to conduct small-scale trials on their fields. By demonstrating the benefits firsthand, we hope to build trust and encourage broader adoption of these practices."
For more information:
Hort Americas
www.hortamericas.com