Plant detective

Even though she grew up surrounded by crops, Denise DeRue is still learning more about plants every day.That’s true whether she’s trialing a new variety, diagnosing a mysterious disease or navigating an unexpected shift in weather or scheduling. This dynamic pace is what she loves most about her role as head grower of Centerton Nursery Inc. in Bridgeton, New Jersey.

“Some of my most exciting days are when I come across something in the greenhouse I haven’t seen before, and I need to diagnose what’s going on with the plant,” she says. “I love solving those puzzles and bringing all that information together. I like to think of myself as a bit of a plant detective.”

Growing up in Rochester, New York, DeRue helped plant, tend and harvest her family’s vegetable garden every year. Visiting her grandparents’ farms in New York and Florida increased her exposure to agriculture, honing her fascination with plants. DeRue followed her passion to Cornell University, where she studied plant science with a concentration in sustainable plant production.

After graduating with a Bachelor’s degree in 2017, DeRue joined BrightFarms as an apprentice grower, and within four months, got promoted to head grower overseeing the production of hydroponic leafy greens in a 1-acre greenhouse in Pennsylvania. Transitioning to her current role at Centerton in January 2021 was quite an adjustment, with a much wider range of varieties and growth cycles to manage.

“It was a little overwhelming at first, because we have so many different species of plants here,” says DeRue, who grows shrubs, perennials and vegetables in 3.2 million square feet of production space (with 2.65 million square feet undercover). “Hydroponics have a quick growth cycle of four to six weeks, and here we have crops that are on the ground for up to two years, so the disease and insect pressures are totally different. Each plant has its own issues, so every day I’m learning something new.”

Sustainable shift

Before DeRue joined Centerton, the nursery relied heavily on chemical applications to combat pests and disease. Now, she’s moving toward “a more sustainable approach” to integrated pest management (IPM) by applying biological controls and beneficial insects to tackle issues.

Leveraging her experience with biocontrols at the hydroponic greenhouse, DeRue started introducing beneficial insects in Centerton’s propagation house, where the moisture attracted uninvited greenhouse guests like fungus gnats and shore flies. “We ramped up the use of rove beetles, called Atheta, and brought them over to our vegetable line as well,” she says. “Then, to attack aphids, we brought in some Aphidoletes and Aphidius.”

Since the Aphidius wasps only target certain aphids, DeRue likes to add generalist predators like Chrysopa for a more widespread attack on common greenhouse pests. “If you have some thrips, some aphids and some mites, the Chrysopa will eat whatever they come across,” she says, “so having that flexibility is great.”

Using her army of insects, DeRue ramped up beneficials and other biological controls throughout the nursery — eliminating chemicals from vegetables and other product lines like Blew Blanket groundcovers, Stone Cottage lavender and Centerton’s pollinator-friendly lines: Bring Back the Butterflies and Caterpillar Candy.

“It’s important for the industry to continue moving in this direction and finding creative ways to produce healthy plants in sustainable ways,” DeRue says. “As consumers get more interested in where their food comes from, it’s going to extend beyond food to where their ornamental plants and other products are coming from and what inputs go into all the things they’re buying.”

Plus, she says, “It’s so gratifying to turn over a leaf and see lacewing eggs or aphids that have been mummified by the wasps. They’re really doing the work for us.”

Continuous improvement

Beyond beneficial bugs, biological controls and other components of her IPM strategy, DeRue and the rest of Centerton’s production team are constantly exploring other ways to improve production. “We’re always looking for new solutions to make the nursery more efficient,” she says.

For example, Centerton recently installed an automated seeding machine that added “some amazing efficiency to our vegetable line,” DeRue says. “It has reduced the amount of time we spend seeding so dramatically that we’ve been able to increase production on that side of the business.”

The automated seeder enabled Centerton to plant more vegetables than previous seasons, resulting in the addition of several new greenhouses to accommodate the nursery’s ongoing growth.

Meanwhile, DeRue and her colleagues are also searching for new varieties that can alleviate certain growing challenges. “We’re always introducing new-and-improved plants with better disease resistance to make a better product for the consumer,” she says.

As the operation expands, DeRue looks forward to exploring new plants and different growing methods to produce the best plant material for the retailers that Centerton supplies. Of course, that means investigating new, sustainable solutions to issues she discovers along the way, using her expanding arsenal of problem-solving “plant detective” skills.