The introduction of beneficial insects, or “beneficials,” is pest control the way nature intended, taking advantage of the natural predator vs. prey order of things. The predators in this case are smaller than a pin prick. “Maybe a couple microns,” Gheorghe said. “Tiny tiny.”
Nevertheless, they have a big job to do. “We want them to establish a good army in the house,” he said.
Natural Pest Control: Know Your Enemy
Before sending any beneficials into battle, Gheorghe identifies exactly which pests he’s targeting. To do that, he scouts the plants daily, peering through a magnifying device resembling a jeweler’s loupe, examining the leaves for even the tiniest hint of damage from unwanted interlopers. “I try to detect the problem first,” he said. “I’m tracking how active they are.
A beneficial is like a hunter. It’s moving so fast.”
After several moments of searching the fuzzy surface of blue borage flowers, Gheorghe comes up empty. There’s not a trace of pest damage on the plants’ foliage. “I couldn’t find any,” he said. “But I guess no bugs, that’s a good sign. I see presence of beneficials.”
So what does the presence of beneficials look like? Think of it as the entomological version of the clean plate club. “Nothing is left behind on the plant,” Gheorghe said.
Broadcasting the Benefits of Natural Pest Control
The beneficials travel to the greenhouse inside canisters filled with dry, loose material that looks a lot like pencil shavings. The insects themselves are too small to see except under magnification, and even then it takes a keen eye to zero in on them.
To disperse the contents onto the edible flowers, Gheorghe empties the canister, shavings and all, into a hand-held device that looks, sounds and works much like an electric hair dryer. It is powered by a battery tucked inside a fanny pack looped around Gheorghe’s waist. As the broadcaster whirs to life, its fan emits a fine gentle shower ─ like chaff on a gentle breeze ─ that settles on the flowers as delicately as morning mist. For maintenance between applications, small packets of beneficials are placed in and around individual flower pots for direct release onto the plants.
Choosing the Right Weapon
Gheorghe said the most important step in using beneficials is determining exactly who the enemy is. Each beneficial feeds on specific pests, so Gheorghe enlists three different varieties to hunt down vandals lurking on leaves, flowers or beneath the soil.
His weapon of choice in this case is Amblyseius swirskii ─ a beneficial predator that consumes small soft-bodied pests such as flower thrips and mites. Another beneficial, Phytoseiulus, consumes spider mites and their eggs, while parasitic nematodes seek and destroy the larvae and pupae of more than two hundred types of soil-borne insects that mature in the ground. (Fun fact: a nematode homes in on its prey by sensing the heat and carbon dioxide it generates.)
Even as larvae, baby beneficials are able to hunt for their supper. Gheorghe said the plants themselves provide all the nutrition needed for them to mature into full-grown fighting machines. “Pollen is a food source for the larvae,” he said. Furthermore, in the absence of pests, adult beneficials will also sustain themselves on pollen and continue to perpetuate their population.
Tracking Pests and Pressure
To track how many and what types of insects are present at any given time, Gheorghe hangs sticky yellow cards the color of caution tape throughout the greenhouse. He inspects the cards monthly to take inventory by counting, for example, the number of thrips per square inch. The tally also gives him crucial information about greenhouse pressure. He explained that a high concentration of unwanted pests on the cards means the pressure is too high and the plants’ health could be weakened, making them vulnerable to infestation and disease. “High pressure means increase the amount of beneficials in that area,” he said.
Gheorghe pursued his training on how to incorporate beneficials through Michigan State University. He has since used his knowledge to train his greenhouse team to closely inspect the plants for any clues that there might be trouble brewing. “Every person, when they are harvesting, if they notice some issues or any bug infestation or high pressure, they will notify me immediately and I’ll go from there.”
A Better Way to Win the War
Prior to incorporating beneficials, Gheorghe said he relied on natural organic soaps and oils to deter would-be pests. Despite the safe organic nature of those alternatives, the results were less effective. Also, releasing microscopic beneficials into the environment is much gentler on the delicate plants than spraying on organic materials.
The switch to beneficials has other advantages as well. The insects are considerably less expensive than other alternatives, and it takes much less time to cover an area with beneficials than with conventional methods. And, once applied, the beneficials can do their work independently, which frees up the greenhouse team to tend to other duties.
“Somebody can be watering someplace else and I can be applying,” Gheorghe said. “It’s safe for my crew, and beneficials can be applied any time of day.”
Gheorghe said the move to beneficials is making a significant difference in the quality and quantity of robust, thriving, healthy edible flowers. “The nasturtiums are the best I’ve seen in years,” he said. (Although, part of the success might be attributable to Gheorghe’s singing. It’s been said he serenades his flowers with country songs.)
Of course, Gheorghe doesn’t want chefs to receive any insects in their flowers ─ not even “good bugs.” He said he wouldn’t mind if it happened to him though. “I’d be happy to find a beneficial rather than a regular bug,” he said.