Capitalizing on Precision Control in Cannabis Cultivation Lighting

When Jason Sanders first started cultivating cannabis in Mendocino County, California, he thought outdoor, sun-grown cannabis was the industry’s future. But the intervening years triggered a significant shift in his thinking.

“What really caught me by surprise is how the market has gone toward quality, rather than field-grown quantity, and how much the controlled environment dictates quality,” Sanders says.

Now director of cultivation at Austin-based Texas Original, Sanders oversees the medical cannabis company’s controlled-environment cultivation facility and R&D, with an environmental focus that transcends seasons.

“It’s a lot more about the environment every day within the crop’s lifecycle and being able to try to control and optimize that environment in order to create a better quality product,” he says.

Advancing with Controlled Environments

Now approaching four years with Texas Original, Sanders has seen the push for quality drive quantum leaps in indoor and greenhouse environmental controls. “The big thing that’s really changed for us in the industry is data collection. We have a lot more data from control companies now,” he explains.

With tech advances, Sanders can monitor and control parameters such as temperature, humidity, CO₂, airflow and light intensity 24 hours a day, acquiring precise measurements that can be reviewed later. The result is a clearer, more complete picture of the entire crop lifecycle.

“That data has allowed us to make better decisions to create the best product we can,” Sanders says. “When I think about controlled environments, it’s our ability to really dial in the parameters in that environment—and replicate it, batch after batch.”

Advances in lighting technologies and precision lighting controls have been especially important. “When I was growing in Mendocino, we didn’t traditionally see supplemental lighting in greenhouses. Now we do. That’s been a shift in the focus for quality,” Sanders says.

Without supplemental lighting, the big, dense flowers achieved today didn’t happen, Sanders says. “The lighting shift within the growing environment has changed a lot. Now, there is more of a focus on supplemental lighting within that environment to achieve the quality that is needed for the market today. That’s a big deal,” he says.

Controlling and Optimizing Light Intensities

There was a time when Sanders, like many growers, didn’t measure light intensity. Now, the ability to measure and control it with precision is crucial as Texas Original plants move through the crop cycle.

As part of a research partnership with Fluence, R&D at Texas Original has identified 1500 to 1800 µmol/m2/s as the optimal light intensity range for flowering. Up to that range, growers capitalize on what Sanders calls the 1% rule: For every 1% increase in light intensity, cannabis yields increase 1%. Above that range, yields begin leveling off and cultivators face diminishing returns and the risk of photobleaching.

Despite multiple studies that support those findings, Sanders estimates most cannabis cultivators grow at 900 to 1,000 µmol/m2/s in flower. He expects to see the market shift toward quality—and the advent of precision lighting technologies that can deliver high intensity efficiently.

To be competitive in today’s market, Sanders believes high light intensity is essential. “Between 800 micromoles [per square meter per second] and 1500, you see a difference in the quality of flower. With more and more flower on the market grown under high light intensities, growers are trying to chase quality right now,” Sanders says.

Though yield is No. 1, high intensity quality goes beyond biomass. “Overall plant yield is higher—as is potency. But the thing I notice is trichome density and enlarged, flared calyxes,” Sanders says. “Flower grown under low light intensity doesn’t have that kind of popcorn ball look. And we definitely get that balled structure under high light intensity.”

But growing under high intensity lighting, which Sanders describes as “very much an LED cultivation model,” requires advanced lighting controls.

Texas Original regularly conducts lighting research at its cultivation facility, in partnership with Fluence. Photo courtesy of Fluence

Incorporating Dimming Controls

Nearly one-third of study participants in Cannabis Business Times’ 2022 “State of the Lighting Market Report” research, which was made possible by Fluence, cited dimming capabilities as a leading factor in their lighting choice. Sanders isn’t surprised that number is growing. He believes that dimming technology is integral to growing at high light intensity.

Photoacclimation as plants move from veg into flower is crucial to Texas Original’s high light intensity strategy—and simplified exponentially by precision lighting controls like the Fluence SHYFT Light Scheduler.

Sanders likens the photoacclimation transition to a freeway on ramp. At Texas Original, plants moving from Week 2 Veg into Week 1 Flower get bumped from 600 to 800 µmol/m2/s. During the first three weeks of flowering, dimming enables a slow increase up to 1500 µmol/m2/s.

“Before we grew under high light intensity, I didn’t photoacclimate,” Sanders says. Texas Original’s veg ran around 400 to 600 µmol/m2/s. Flower maxed out between 800 and 900 µmol/m2/s. But with high light intensity in flower, photoacclimation isn’t optional.

“The plant doesn’t want to go into Week 1 flower out of the gate at super high light intensity. It’s a shock to the plant. We’ve got to slowly acclimate the plant to that new environment. And we do that through dimming,” he explains.

What was once manual, and subject to human error, is now fully automated with SHYFT. “Having that automation, being able to preset that schedule, allows it to just ride the schedule without us having to adjust the setpoints manually every day,” Sanders says. “That was a big jump for us.

“It’s consistency and quality that we’re shooting for now. And by having a controlled environment that we’re able to tightly control, we can really make better decisions to achieve higher quality at these setpoints and replicate these actions,” Sanders says.

Tightening Programs Through Controls

With an emphasis on high light intensity, Sanders says growers can capitalize on their environment’s potential and tighten up programs with precision controls. As an example, he points to SHYFT’s ability to simulate sunrise and sunset within his indoor grow.

“These plants have grown for thousands of years outside, and it’s just genetically ingrained in them to have a sunrise and sunset,” he says. “As growers, we’re always trying to mimic the exterior environment as best we can indoors.”

And while Sanders says it’s just cool to slowly wake up your plants and slowly put them to sleep, he sees a greater benefit: SHYFT’s sunrise-sunset control helps reduce the humidity spike growers typically face when lights go off in a warm environment full of transpiring plants.

“During the sunset time with the SHYFT controller, it slowly allows that environment to neutralize and not just have a sudden shift in it.” That reduces the humidity spike and the risk of botrytis or powdery mildew outbreaks that can complicate late flower cycles.

Sanders also notes another integral control component for high intensity growers: a manual feature. “That’s nice for when we’re doing our IPM applications,” he says. Growers can manually turn growing room lights down, do their application, and let plants dry before high intensity lights are turned back up.

For Sanders, controlled environments optimized through precision controls are key to Texas Original and other cultivators achieving their best output.

“I think where we’re at right now, as growers, we’re just trying to run as tight of a program as we can,” Sanders says. “The way that we improve as growers is by tightening that program up—being sure that we’re looking at the crop cycle every day, hitting our desired setpoints. The better we’re able to monitor those and control them, the better growers we are.”