By Jessica McKeil

Hemp Growers across America have a problem. Environmental influences combined with genetic variability put entire fields at risk of running hot. According to C&EN Agriculture, experts predict that as much as “40% of the hemp grown in the US will test above the 0.3% total THC threshold.”

Growers like Matt Gunter, owner of Triangle Cannabis in North Carolina, know all too well the challenge of keeping hemp under current legal THC limits. Gunter works with CBD and CBG cultivars and was first licensed under the 2018 Farm Bill. He is currently transitioning to the federal USDA hemp program, a completely new licensing regime with even more layers.

To continue legal production under the new federal requirements, he can’t just “grow willy nilly.” Gunter has to be extremely careful about what environmental stressors he exposes his genetics to. To create a consistent and more predictable harvest, he’s growing in controlled environment settings and experimenting with advanced LED technology. 

Advances in LED technology are giving cultivators incredible power to manipulate and enhance the photosynthetic spectrum. With the dialed-in light recipes possible with this new wave of LEDs, it means farmers like Gunter have the ability for precision phytochrome manipulation to get peak CBD and CBG without running hot.

Michael Naich, American Growor’s founder and chief scientist.

The Experiment: American Growor Dynamic Spectrum ONE vs. Traditional 600w HPS

In Gunter’s own words, he is “suspicious of marketing specifications,” especially when it comes to grow lights. As most growers are well aware, the grow light industry as a whole is rife with unsubstantiated claims and inaccuracies in the available specs. 

It’s why Gunter, a trained engineer and self-proclaimed skeptic, runs ongoing scientific experiments on “different genetics and different environments, both indoor and outdoor.”

This summer, he set up a comparison between a traditional 600w HPS light and the Dynamic Spectrum One, a new LED system by American Growor. Starting with four clones in each controlled indoor environment, Gunter wanted to see, “watt for watt, what really happens in terms of potency and mass.”

First, he documented a rapid growth rate of more than three centimeters a day in the mid-span of the vegetative phase under the advanced LED light system. This was a significantly faster growth rate than what he had come to expect under an HPS system.

Second, Gunter measured both potency and the consistency of potency between each room. To test, he took several samples during the last two weeks of flower, running each through a Gemmacert analyzer to determine THC, CBD, and CBG levels.

In the HPS room, bud potency was not consistent. In his words, it was “a wild card.” From one flower to the next, CBD and THC levels varied. He has come to expect these large discrepancies in CBD and THC profiles. The average A size CBD inflorescence under HPS was 5.65 percent, “but, of course, it was divergent all over the map.”

Under the American Growor fixture, he discovered that the potencies of all buds converged into a single consistent level come harvest time. In addition, all qualities of flower (bud A, B, and C types), sampled from all over the canopy, produced a consistent 8.26 percent CBD. Which, in Gunter’s experience, is incredibly high for a compliant grow. 

Third, after meticulously harvesting bud by bud, he also reported a 14 percent greater total bud mass of the LED over the HPS system. On average, each plant under the American Growor fixtures produced 2.9 lbs of flower.

Cannabis cultivation by American Growor.

LED Technology Improves Consistency

Smart LED technology combined with refined light recipes provides hemp cultivators with stability and predictability that is not available in outdoor environments. But as Gunter’s experiment demonstrates, the American Growor system (and associated recipes) also creates more inner-crop cannabinoid consistency, potency, and yield.

LED technology like this finally gives hemp producers the steering wheel to delicately direct the final harvests in a highly controlled manner. As per Gunter, “With the LED like American Growor, you’re not just fixed within a fixed spectrum. You want that dynamic spectrum, because each cultivar will respond differently depending on what light you give it.”

Which, for hemp farmers, means fewer surprises. When a few percentage points can push a whole crop toward illegality, control is absolutely a critical component. The new advances offered through AI-driven LED systems, like the Dynamic Spectrum One, will help hemp farmers finally take control over the crops to achieve greater yields, better consistency, and more CBD, without putting it all on the line.