5 Mistakes Cultivators Make With Lighting

5 Mistakes Cultivators Make With Lighting

Understanding and avoiding these common errors can help growers achieve maximum yield and increase revenue per square foot.


Cultivators should consider many factors when making decisions about their lighting systems, and with many options and measurements to take into account, mistakes are bound to be made. Travis Williams, VP of Marketing for Fluence Bioengineering, discusses common mistakes cultivators make with lighting and how avoiding these pitfalls can help growers increase revenue per square foot.

Mistake No. 1: Not staying up-to-date.

Not exploring new techniques and technologies most often prevents growers from achieving maximum revenue per square foot, Williams says. Controlled environment agriculture is evolving at a rapid pace as new technologies and techniques come online almost daily. Record-breaking yields that were achieved last year are constantly being improved upon, and continual improvements must be made to stay ahead of the competition.

“If you’re not moving forward and you’re just staying in place, you’ll get passed by. If you’re not willing to explore new forms of ag tech that's coming online, you’ll get passed by,” Williams says. “We’re already seeing the industry average grams per square foot increase year-over-year, and due to new ag technologies and practices, that trend will continue.”

By focusing on constant innovation and exploration, and by never being satisfied with where you are today, cultivators can stay ahead in the fast-paced and competitive cannabis space, especially as prices continue to drop, he adds. 


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“You really have to be more efficient with what you’re doing, both efficiency in terms of real estate and square footage [and] in terms of energy and labor, whether that’s looking at vertical farming to increase output from a fixed square footage of cultivation space, or supplemental lighting in a greenhouse to increase year-round production,” Williams says. “The opportunities to increase outputs while reducing inputs are greater than ever thanks to LED technology.”

Mistake No. 2: Not measuring light intensity.

“A lot of growers are simply not aware of the light intensity they’re growing under,” Williams says. “Light intensity has a direct impact on yield. Generally, the more light that you provide to a crop within certain parameters, and as long as other environmental factors are adjusted appropriately, you’ll get more yield.”

Light intensity is measured in photosynthetic photon flux density (PPFD), or the amount of photosynthetically active radiation (PAR), that actually arrives at the plant, and can be checked using a quantum sensor. Williams says there are several types of light meters that can measure light in many ways, from the spectrum to how it is perceived by plants and even human vision, so it’s critical growers are using the correct meter measuring PAR, which defines the type of light needed to support photosynthesis. Lighting designers proactively help growers understand and optimize PPFD values for various stages of growth via lighting models.

Mistake No. 3: Not conducting lighting trials.

Plants are life forms, and not all genetics will have the same results under a given PPFD. Performing lighting trials will help cultivators understand if they have a high-yielding crop or one that will hit a light saturation point sooner than other genetics, Williams says.

“That will really give you insight from an R&D perspective on how to optimize your cultivation facility on a large scale,” Williams says. “By deploying a small room in a beta or trial phase, you can adjust light intensity and the different environmental conditions to determine what … standard operating procedure gets the best results.”

Williams adds that although growers are always adjusting protocols, cultivators on a commercial scale should never use their production facility as a test bed to adjust factors like light intensity if they are unsure of the outcome. He encourages customers to separate their production from R&D and trialing.

A vertical grow with multiple tiers

Mistake No. 4: Not receiving a lighting consultation from their lighting manufacturers.

“We’re photobiology experts, we’re lighting experts, and we work with all of our customers to truly understand their goals and the intricacies of their facilities,” Williams says.

He says many of Fluence’s customers approach the company with a basic question or general interest in a light—and usually that initial conversation leads to a cultivation transformation by the time the transaction is made. A customer considering a single-tier rolling bench strategy, for example, could decide after a consultation with Fluence that a vertical farm with three tiers will triple the grams per square foot coming from the same space.

“That’s not something that they typically consider if we didn’t have the opportunity to speak with them,” Williams says.

Manufacturers like Fluence can also help educate cultivators about photobiology and the parameters they need to consider when they change their lighting systems, Williams says. He says most growers are accustomed to high pressure sodium (HPS) lights and have based their standard operating procedures accordingly.

“Growers have developed their cultivation strategy to fit HPS lighting, so when they replace HPS lighting with one of our LED systems, they subsequently need to adjust other major input variables. A lot of growers don’t realize the need to adjust environmental conditions such as raising ambient temperature, increasing CO2, and adjusting fertigation and irrigation to optimize conditions for improved growth and development.”

“Being in the infused-products business, the success of our cultivation efforts really comes down to milligrams of active ingredients such as THC or CBD,” said Cyrus Frudi, president of Franklin BioScience. “Fluence has enabled us to achieve higher yields and potency, driving up these top line metrics, while simultaneously driving down the costs associated with producing them.”

Mistake No. 5: Analyzing the wrong metrics.

Williams says many cultivators need to deploy better metrics for analysis. With the introduction of LED technology, the industry-standard grams-per-light and grams-per-watt analysis needs to be addressed.

Williams says focusing on grams (or pounds) per light is misleading as new lighting systems come to market.

"Ultimately growers are operating from a fixed real estate, so the key variable is the amount of product they produce per square foot, not per light or per watt. Every light is different, but a square foot is a square foot,” he says. 

“If I can produce 80 grams per square foot, does it matter if that was generated from one light, two lights or three lights? Yes and no,” Williams adds. “You also need to ask how much energy did each light consume, how much did each light cost, and what were the associated operating costs? Looking at grams or pounds per light is limiting and incomplete.”

Grams-per-square-foot is the most appropriate metric to use to understand yield because it will offer an assessment of how efficiently space is being used and it removes other variables from the equation, such as the number of lights being used, Williams says.

“A lot of growers will focus on grams per watt, and while that’s a great metric to understand the energy efficiency of your lighting system, it is a secondary metric to grams-per-square-foot,” Williams says.

The problem with grams per watt, he says, is that a cultivator can achieve a high grams-per-watt figure but get a low overall yield. The primary focus for growers, he said, is to achieve high yield, so there must be balance between achieving high yield and having a healthy grams-per-watt efficiency metric. If a cultivator is solely focused on grams per watt, they could miss out on higher yields.

Photos courtesy of Fluence Bioengineering