CBD OIL

According to the 2020 “State of the Cannabis Lighting Market” study conducted by Cannabis Business Times and made possible by Fluence by OSRAM, most cannabis cultivators are growing indoors, as 85% of participants said they operated this type of facility. However, an increasing number of growers also are running year-round greenhouses, as nearly a third (29%) indicated they grow in greenhouses with supplemental lighting.

Taylor Kirk, horticulture service specialist with Fluence by OSRAM, says while there are lighting fundamentals that apply no matter what type of facility growers are operating, there are certain strategies that indoor growers must use to be successful that are different than approaches greenhouse growers take.

“When you’re in a greenhouse supplementing with LEDs or another source, you are basically working with what you have from Mother Nature with sunlight, and then figuring out what you could add to offset low light levels at certain times, like cloudy days or certain times of the year where you just don’t get as much sunlight. And that becomes a lot more challenging because you have to take a holistic approach to how much light the plant receives in a given day,” Kirk says. “With sunlight, you have sunrise and sunsets and this natural bell-shape curve of light intensity throughout the day, and there are a lot of different ways to manage it.”

While most growers consider light spectra, or the quality of light, light intensity and photoperiod when planning lighting strategies, Kirk says one of the most important inputs for boosting yield whether growing indoors or in greenhouses is light intensity. Growers who dial up this parameter carefully can see higher yields and other benefits.

Here, Kirk shares seven lighting tips and strategies for cannabis cultivators, whether they are growing indoors or in greenhouses.

1. Optimal lighting spectrum varies by facility type.
While indoor growers rely on lighting fixtures exclusively, greenhouse growers receive some of their power from the sun. Because sunlight provides a wider spectrum naturally, greenhouse growers are often interested in options other than broad-spectrum light-emitting diodes (LEDs), Kirk says.

“There are very efficient fixtures that you can run in a greenhouse that are more red/blue leaning, giving you that pink light source,” he says. “But since you’re supplementing sunlight [in a greenhouse,] that works out. But we know for sure from all of [Fluence’s] research that the best light spectrum for indoor cultivation is a broad spectrum, as white light is the best suited for indoor cannabis growth.”

Broad spectrum lights provide a balance of blue, green and red light, mimicking the sun, with the exception of far red and UV light. “We’ve done some trials on far red and UV as well, and we just haven’t seen the benefit that outweighs some of the downsides of it,” Kirk says.

2. Lighting intensity plays a large role in maximizing production and yields.

As cannabis ages, it can take a higher amount of light, Kirk says. According to a recent light intensity study conducted by Fluence in partnership with Texas Original Compassionate Cultivation, research suggests growers can in some cases double the intensity traditionally used.

“We have some early successful data, and we have ideas of how much light this plant can take. It’s pretty remarkable compared to other crops,” Kirk says. “It’s way more light than anything else can take.”

“If you’re really interested in pushing ultra-high light intensities to see this maximum yield potential from cannabis, you better be ready because everything that you’re doing impacts that performance and that yield potential. It’s not just how much light you’re giving them.” — Taylor Kirk, horticulture service specialist, Fluence by OSRAM

3. When increasing light intensity, take a cautious, steady approach, and remember to factor in genetics.

While some growers keep a constant light level in propagation, Kirk says cultivators can experiment with starting at a low intensity in this stage and increasing light gradually to better acclimate and prepare plants for more intensity in the vegetative and flower phases.

“We recommend 50 micromoles a day of increase in veg and about 100 micromoles a day in flower, but all of this is cultivar-dependent. And I do like to emphasize that because cannabis genetics are so diverse,” Kirk says. “You have to be careful not to do it too fast because you can stress the plant and set yourself back and lower your yields. Some cannabis [cultivars] can handle a higher light intensity than others.”

The Green Organic Dutchman’s (TGOD) cultivation facility. As cannabis ages, it can take a higher amount of light. According to a recent light intensity study conducted by Fluence in partnership with Texas Original Compassionate Cultivation, research suggests growers can in some cases double the intensity traditionally used. Courtesy of Fluence by OSRAM

4. Greenhouse growers must factor in DLI when increasing intensity.

Daily light integral, or DLI, is a measure of how much light plants have received within the entire photoperiod, and it is measured in moles per day. Greenhouse growers use this measurement to supplement cloudy days and account for the natural cycles of the sun.

“The plant doesn’t really care how the light is given, as long as that photoperiod isn’t interrupted too much and they are getting a certain amount of light required for growth,” Kirk says. “Indoor growers don’t focus on DLI as much because typically they will provide the same amount of light for the entire photoperiod.” (Although some growers use controls to mimic sunrises and sunsets, more research is needed to determine the efficacy of this approach, Kirk adds.)

Greenhouse growers need to factor in DLI when dialing up intensity. “If you have the same amount of light intensity given to the plant throughout that entire photo period, they’re going to get more light in veg than they are going to be getting in flower at the same light intensity” because the photoperiod is 12 hours in flower versus 18 in veg, he says. “We typically increase the light intensity day one of flower a little bit, and that way, we’re still decreasing DLI. Using an example here, say you’re leaving the veg room at 500 PPFD, you would need to start at 750 in flower.”

“All of this is cultivar-dependent. And I do like to emphasize that because cannabis genetics are so diverse.”  —Taylor Kirk, horticulture service specialist, Fluence by OSRAM

5. For growers using tiers, veg time is important.

Growers can adjust the time plants spend in the vegetative phase to help control plant size. While cultivators using tiered systems can also increase intensity, they must be careful not to let the plants spend too long in that lifecycle stage, Kirk says..

“You want to keep smaller plants, otherwise they are going to outgrow the space that you provide them,” he says. “If you veg for too long, your plant is going to be pretty large when you initiate flowering and stretch even more. They always go through a growth spurt when the photoperiods change, so you need to keep plants shorter on a rack system.”

While cultivators using tiered systems can still increase intensity, they must be careful not to let the plants spend too long in that lifecycle stage.Courtesy of Fluence by OSRAM

6. Consider growing environment parameters when adjusting light intensity.

When dialing up intensity, growers must account and control for other factors, like temperature, humidity, irrigation and nutrients.

“The last thing we want to do is to tell a grower to use light intensity that’s twice as much as they are historically used to using because we know we can get a lot more yield with that, but we’re going to cause that grower to fail if we don’t guide them through other factors that need to be adjusted, as well,” Kirk cautions. “There are many factors that need to be managed carefully when you push the plant in this way.”

The potential benefits are massive, as Kirk says growers can yield up to twice as much as commercial growers have historically yielded. That’s why he and the horticulture service team at Fluence spend so much time coaching growers through the process of increasing intensity.  

For example, vapor-pressure deficit, or VPD, is a metric they watch closely to be sure that intensity isn’t negatively impacting the relationship between temperature and humidity. He suggests keeping the VPD in the “less stressful” ranges of .9 to 1.3 kPa.

7. There’s a direct correlation between increasing intensity and the need for increased nutrients and water. Be sure to feed and irrigate plants more. 

Growing environment isn’t the only parameter that must be considered when adjusting light intensity, however.

 “The program that [growers] run, all the cultural practices, what kind of media they are using and fertilizer and concentration of fertilizer—all of these things need to be looked at if you’re thinking about increasing light intensity,” Kirk adds.

When growers provide the plant with more energy from light, they must supplement nutrients and water as well. However, each cultivar has different needs.

“I like to compare it to a bodybuilder. Normally, humans need probably 2,000 calories a day, and that’s your average diet, but if you’re a bodybuilder, you’re not going to be able to see the results that you’re after with 2,000 calories a day,” he says. “So you’re going to need to increase your concentration of calories and nutrients.” Kirk says the same goes for plants, as they need increased inputs when receiving more light.

Although the “meat, potatoes and vegetable” nutrients plants need like potassium, magnesium and calcium are key, nonessential plant nutrients also are important to help plants tolerate more intensity.

“Earlier research was done with soilless mix that had quite a bit of organic amendments and biostimulant additions. It wasn’t just fertilizer and water in a sterile environment [but also] the plant and microbial relationship as well, and there’s a lot of benefits in there that reduce stress,” Kirk says. “I definitely encourage the use of biostimulants.”

Amino acid and fulvic acid may be non-essential additives, for example, but they can be beneficial, especially when increasing intensity.

“If you’re really interested in pushing ultra-high light intensities to see this maximum yield potential from cannabis, you better be ready because everything that you’re doing impacts that performance and that yield potential,” he says. “It’s not just how much light you’re giving them.”

A pair of House Republicans aren’t holding their horses on cannabis reform activity in the Senate.

Reps. Dave Joyce, R-Ohio, and Don Young, R-Alaska, introduced a bill May 12—the “Common Sense Cannabis Reform for Veterans, Small Businesses and Medical Professionals Act”— that would remove cannabis from the list of scheduled substances under the Controlled Substances Act.

In addition, the legislation would also protect depository institutions that provide financial services to “legitimate” cannabis-related businesses; provide safe harbor for veterans to use, possess or transport medical cannabis in compliance with state laws; and direct two studies on cannabis as it pertains to pain management and impairment through the National Institutes of Health (NIH), according to the bill’s text.

Joyce and Young’s efforts come as Senate Majority Leader Chuck Schumer, D-N.Y., and fellow Sens. Ron Wyden, D-Ore., and Cory Booker, D-N.J., continue to work on drafting a federal reform bill to end prohibition in the upper chamber. They released a joint statement regarding their comprehensive reform efforts in February but have yet to introduce the measure.

Comprehensive cannabis reform took hold in the House last Congress via the Marijuana Opportunity, Reinvestment and Expungement (MORE) Act, which would have removed cannabis as a Scheduled I controlled substance and eliminated criminal penalties for an individual who manufactures, distributes or possesses cannabis. While it passed the House last year, 228-164, the bill never advanced in the Republican-controlled Senate.

The chief sponsor of the MORE Act, Rep. Jerrold Nadler, D-N.Y., plans to reintroduce the 87-page legislation this Congress, he said during a House Judiciary Subcommittee meeting in March.

In the meantime, Joyce and Young introduced their bill Wednesday. The 14-page legislation isn’t as long-winded but puts the removal of cannabis as a controlled substance, banking protection, reform for veterans and mandated NIH studies at the forefront. It does not include social justice and equity provisions.

“With more than 40 states taking action on this issue, it’s past time for Congress to recognize that continued cannabis prohibition is neither tenable nor the will of the American electorate,” Joyce said in a press release.

“My legislation answers the American people’s call for change and addresses our states’ need for clarity by creating an effective federal regulatory framework for cannabis that will help veterans, support small businesses and their workers, allow for critical research and tackle the opioid crisis, all while respecting the rights of states to make their own decisions regarding cannabis policies that are best for their constituents,” he said. “I look forward to working with my colleagues on both sides of the aisle to get this bill signed into law so that we can enact sensible and meaningful cannabis reform that will improve lives and livelihoods.”

Joyce’s advocacy for cannabis reform is not new. He also co-sponsored the Secure and Fair Enforcement (SAFE) Banking Act and was vocal in his support of that legislation on the House floor when it cruised to passage by a 321-101 vote last month.

In 2018, the House Appropriations Committee passed a provision known as the Joyce Amendment (formerly the Rohrabacher-Blumenauer Amendment), which prevents the U.S. Department of Justice from spending federal funds on prosecuting state-legal medical cannabis businesses.

A former U.S. House member, Dana Rohrabacher, a Republican from California, launched the Congressional Cannabis Caucus in 2017 with fellow Reps. Earl Blumenauer, D-Ore., Jared Polis, D-Colo., and Young, who now co-chairs the caucus with Joyce.

“For too long, the federal government’s outdated cannabis policies have stood in the way of both individual liberty and a state’s 10th Amendment rights. It is long past time that these archaic laws are updated for the 21st century,” said Young, whose home state of Alaska legalized adult-use cannabis through a ballot measure in 2014. “This bill takes significant steps to modernize our laws by removing cannabis from the Controlled Substances Act and allowing the VA to prescribe medical cannabis to veterans, in addition to finally permitting state-legal cannabis businesses to utilize traditional financial services.”

The bill would also direct the U.S. Food and Drug Administration and the Alcohol and Tobacco Tax and Trade Bureau to issue rules to regulate cannabis modeled after the alcohol industry within one year of enactment.

Steve Hawkins, the executive director of Marijuana Policy Project, said in a statement that he’s encouraged to see Republican leadership to end the federal prohibition and criminalization of cannabis. Reform is a bipartisan matter ripe for immediate solution, he said.

“With an overwhelming majority of Americans supporting the end of cannabis prohibitions, it’s clear that our country has a mandate to create a legal industry that supports both medical and adult-use,” Hawkins said. “It’s a bipartisan issue and the ‘Common Sense Cannabis Reform for Veterans, Small Businesses and Medical Professionals Act’ introduced by Reps. Dave Joyce and Don Young is a promising step forward.”

Tune into Fluence by OSRAM‘s next free webinar, where the team will answer some of the most fundamental questions about what lighting solutions best suit your cultivation goals.

In this presentation, Fluence’s horticulture service experts will discuss the evolution of cannabis lighting technology and share best practices when evaluating the right light for your farm. The team will show you how to optimize your environment when upgrading to an LED lighting strategy and will also share some grower case studies illustrating the benefits achieved by cultivators who have taken these steps. 

Join the free webinar at 11 a.m. CT Thursday, May 20!

In this “Flower-Side Chats” series of articles, Green interviews integrated cannabis companies and flower brands that are bringing unique business models to the industry. Particular attention is focused on how these businesses integrate innovative practices in order to navigate a rapidly changing landscape of regulatory, supply chain and consumer demand.

Multi-state operators (MSOs) are on the rise in the United States, navigating complex regulatory frameworks to drive profitability through economies of scale and scope. As an MSO and an early mover in the space, a significant part of MariMed’s current strategy is to complete the acquisition and consolidation of the licensed state cannabis businesses it has developed. It takes seasoned leadership to make that happen, and MariMed’s is led by one of the most experienced and successful MSO management teams in the industry. Over the last eight years, Bob Fireman and his colleagues have won 17 licenses in 6 states, and designed and developed over 300,000 square feet of cannabis cultivation, production and dispensing facilities.

MariMed has also developed a portfolio of award-winning cannabis brands and infused products which are licensed, manufactured and distributed in Delaware, Illinois, Maine, Maryland, Nevada, Rhode Island and Puerto Rico. A recently announced $46 million financing for a facility with Hadron Healthcare Fund will help repay all MariMed debt other than mortgage-backed bank loans and one convertible note, as well as help upgrade and expand the company’s owned and managed cannabis facilities.

We spoke with Bob Fireman, CEO of MariMed. Bob started the foundations of MariMed in 2008 after getting into large-scale hydroponics for urban sustainable agriculture. Prior to MariMed, Bob served as a startup lawyer focused on tech and emerging industries.

Aaron Green: Bob, tell me about how you got started in the cannabis industry.

Bob Fireman: I practiced law for decades. Part of my practice was to help startups in all sorts of industries, particularly technology and new emerging markets. At one point, I was introduced to a fascinating sustainable food business opportunity – to build hydroponic farms on rooftops in cities across the country.

When one of our projects in San Francisco hit some roadblocks, our team there pivoted to what was becoming the Wild West of California cannabis. My friend and current MariMed CFO, Jon Levine, and I began investing and managing a cultivation site there. That’s where we built our early foundation of industry knowledge.

Fast forward a few years, and I was afforded the opportunity to be involved in the drafting of the proposed Massachusetts medical cannabis legislation.

Through that work, we met a team that had won one of three cannabis licenses in Rhode Island. We formed a real estate LLC and raised the capital to develop a seed to sale cannabis facility in Providence, which was later leased to the Slater Center, a not-for-profit medical cannabis licensed business. Today, the Slater Center is a nationally acclaimed operation that services over 10,000 medical patients.

From there, we took our know-how and formed a new entity that was the formal beginning of the company we now know as MariMed. Initially, we helped win licenses for clients in Massachusetts, Delaware, Maryland, Illinois and Nevada. We also provided management services, working capital and other necessities. Under our management, we organically built these businesses from the ground up, advancing best practices and somewhat quietly creating a network of best-in-class operations throughout the industry.

That led to the consolidation of those businesses that we’re focused on today as a core strategic pillar.

I’m incredibly proud of our team, the core of which has been at this for 10 years. We’ve watched other MSOs try different models of success, with varying degrees of success. For us, focusing on growth markets, building at a reasonable and scalable clip, attracting incredible talent at all levels of the company, and developing fantastic brands that customers love, are the ingredients that have translated to where we are now – strong performance and an exceptionally bright future. “Slow and steady wins the race” has become a mantra.

Green: What trends are you looking at right now? What’s on your radar?

Fireman: My radar has a singular focus, and that’s to create shareholder value. That’s why completing the consolidation of the cannabis licensed businesses we’ve developed and manage into our public company is so critical. Back in the day, the initial available licenses were in medical-only state programs where applicants were required to be not-for-profit state companies. Accordingly, we raised the capital in the real estate entity which leased facilities to the licensees. Our revenue was from rents, management services and licensing fees.

In 2019, we implemented a new strategic plan to consolidate these businesses. While that translates to our being structured similarly to other MSOs in that we are a vertically integrated seed to sale company, we are distinct in our operational excellence, quality product portfolio, and strong balance sheet. Other MSOs have raised large amounts of capital to pay large sums to acquire licensed state cannabis businesses and have found themselves over-leveraged and challenged to assimilate other companies’ methodologies and cultures. By consolidating the businesses and talented people we developed and managed from day one and utilizing our best practices and processes system-wide, we realize enormous capital efficiencies.

Our strategy is paying off. Our core cannabis revenue in 2020 increased 207% to $50.9 million, and our 10k reported EBITDA of $16.3 million. And now we’re on track to double our revenue in 2021.

The last piece of the puzzle is to let the world know what we’ve been doing. Slow and steady has worked for us but gone are the days of doing so quietly. We’re proud of what we’ve accomplished and exceedingly bullish on what’s to come.

Green: What do you look for in an M&A target?

Fireman: When M&A makes sense for us, we first look for single operators and entrepreneurs in states where we are not active and look to partner with business leaders that had the vision and the courage to get into this industry and build solid cannabis businesses from the ground up. I’m looking for businesses that could benefit from being part of a larger, more experienced and well-capitalized company like MariMed. Obviously, as an MSO with a solid platform, MariMed is approached regularly by other MSOs and banks suggesting candidates for M&A opportunities. Lining up with a company that has complementary cannabis licenses in other states and who shares our vision and ethics could be a win-win situation. They must embrace our commitment to diversity, the environment and proper corporate governance. We have been somewhat reticent to do this until we see some increase in our share price and market capitalization.

Green: Are there any new products, or product trends that you’re looking at?

Fireman: Marimed looks to be the most trusted source of high-quality cannabis products that consistently delivers innovative health and wellness solutions to our patients and customers. Our lab scientists are constantly creating and testing new and innovative formulations of cannabinoid compounds including CBD, THCa, CBG, CBN and others that will improve the health and wellness of our customers.

Our brand portfolio is ever-expanding with new and better product offerings. Our award-winning Betty’s Eddies Fruit Chews brand is adding new SKUs of varieties and flavors for both medical and adult use programs. Our Nature’s Heritage flower and concentrates brand is adding a line of solventless concentrates, live rosin, as well as new formulations for RSO, an oil popular with medical patients. Kalm Fusion is expanding its successful line of powdered drink mixes as we see more movement in the cannabis beverage category.

Microdosing is hugely popular right now, and we’re rolling out products in the 2-5mg dosage range. Health and dietary concerns are top of mind as well, and we offer products that are vegan, sugar-free and gluten-free. Ultimately, we want to be sure that we have something on the shelves for every single consumer. The financial hardship created by the pandemic has made consumers more attracted to value added products such as popcorn buds.

Green: You recently announced an equity financing from Hadron. I’m curious to learn more about it from a nuts-and-bolts perspective if you can share any of that information.

Fireman: Over the last year, access to the capital markets for equity raises in cannabis public companies was difficult. The cost of debt was and is still high, and we were looking for a long-term financial partner that understood the industry and could assist us. Hadron Capital has been successful for several years investing in some of the most successful MSOs and they saw the value and potential in MariMed’s experienced management and great assets.

Hadron invested $46 million in equity in MariMed this March. Approximately $16 million was utilized to retire all our short- and long-term debt but for bank secured debt and one convertible note. $7 million is committed to funding our capex and expanding the capabilities of our facilities, enabling us to grow more flower and automate production. The balance of funding will support our consolidation strategy to fund two more roll ups of state licensed cannabis businesses into the public company.

Going forward, it is comforting to have a capital partner to assist us in future acquisitions and M&A opportunities.

Green: I’d love to learn more about your Nature’s Heritage brand, particularly as it relates to the cultivation and the flower products.

Fireman: Our COO Tim Shaw has assembled a cultivation and production team with expertise in all aspects of genetics, growing methodologies, extraction techniques, and packaging innovation. That’s provided us a rich collection of quality genetics that make up Nature’s Heritage, our top-selling flower, oil and concentrate brand in Massachusetts and Maryland. We’ve recently expanded the line to include Rick Simpson Oil (RSO) and solventless concentrates (including live rosin) and have been receiving stellar feedback.

Green: What are you interested in learning more about?

Fireman: Over the last decade, the MariMed core team has seen the emergence and amazing growth of the cannabis industry. The initial medical programs in California and Colorado have now led to some form of legal medical or adult use cannabis programs in over 33 states and districts.

We are most interested in learning and following the federal, state, and international laws and regulations. It is vital to know how these laws will affect our company and the industry as a whole. When might full federal legalization become a reality? What might different versions of the law be? Will state legal programs be protected as well as the companies that took the risk in investing in the industry at its nascent state and how? What will FDA requirements and regulations look like? What medical claims will companies be allowed to make, and what kind of research or trials will be required to put a product on the shelf? What are the ramifications of the MORE Act or the SAFE Banking Act?

Responsible MSOs need to be prepared to rise to or above the standards of care of other industries. A lot of this was impossible in the past because of federal prohibition laws. Soon, if not already, labs and manufacturing processes will need to be GMP certified and more. Consumer data will need to be HIPAA compliant. Cannabis companies have to be good corporate citizens: diversity and equal opportunity should be embedded in business decisions, and commitment to ESG and sound environmental and social policies with good corporate governance need to be in planning and implemented.

Following the laws and holding ourselves to the highest possible safety and business standards will allow the cannabis industry to finally become “mainstream.”

Green: Alright, great. Thank you, Bob. That concludes the interview!

According to the 2020 “State of the Lighting Market” study conducted by Cannabis Business Times and made possible by Fluence by OSRAM, most cannabis cultivators are growing indoors, as 85% of participants said they operated this type of facility. However, an increasing number of growers also are running year-round greenhouses, as nearly a third (29%) indicated they grow in greenhouses with supplemental lighting.

Taylor Kirk, horticulture service specialist with Fluence by OSRAM, says while there are lighting fundamentals that apply matter what type of facility growers are operating, there are certain strategies that indoor growers must use to be successful that are different than approaches greenhouse growers take.

“When you’re in a greenhouse supplementing with LEDs or another source, you are basically working with what you have from Mother Nature with sunlight, and then figuring out what you could add to offset low light levels at certain times, like cloudy days or certain times of the year where you just don’t get as much sunlight. And that becomes a lot more challenging because you have to take a holistic approach to how much light the plant receives in a given day,” Kirk says. “With sunlight, you have sunrise and sunsets and this natural bell-shape curve of light intensity throughout the day, and there are a lot of different ways to manage it.”

While most growers consider light spectra, or the quality of light, light intensity and photoperiod when planning lighting strategies, Kirk says one of the most important inputs for boosting yield whether growing indoors or in greenhouses is light intensity. Growers who dial up this parameter carefully can see higher yields and other benefits.

Here, Kirk shares seven lighting tips and strategies for cannabis cultivators, whether they are growing indoors or in greenhouses.

1. Optimal lighting spectrum varies by facility type.
While indoor growers rely on lighting fixtures exclusively, greenhouse growers receive some of their power from the sun. Because sunlight provides a wider spectrum naturally, greenhouse growers are often interested in options other than broad-spectrum light-emitting diodes (LEDs), Kirk says.

“There are very efficient fixtures that you can run in a greenhouse that are more red/blue leaning, giving you that pink light source,” he says. “But since you’re supplementing sunlight [in a greenhouse,] that works out. But we know for sure from all of [Fluence’s] research that the best light spectrum for indoor cultivation is a broad spectrum, as white light is the best suited for indoor cannabis growth.”

Broad spectrum lights provide a balance of blue, green and red light, mimicking the sun, with the exception of far red and UV light. “We’ve done some trials on far red and UV as well, and we just haven’t seen the benefit that outweighs some of the downsides of it,” Kirk says.

2. Lighting intensity plays a large role in maximizing production and yields.

As cannabis ages, it can take a higher amount of light, Kirk says. According to a recent light intensity study conducted by Fluence in partnership with Texas Original Compassionate Cultivation, research suggests growers can in some cases double the intensity traditionally used.

“We have some early successful data, and we have ideas of how much light this plant can take. It’s pretty remarkable compared to other crops,” Kirk says. “It’s way more light than anything else can take.”

“If you’re really interested in pushing ultra-high light intensities to see this maximum yield potential from cannabis, you better be ready because everything that you’re doing impacts that performance and that yield potential. It’s not just how much light you’re giving them.” — Taylor Kirk, horticulture service specialist, Fluence by OSRAM

3. When increasing light intensity, take a cautious, steady approach, and remember to factor in genetics.

While some growers keep a constant light level in propagation, Kirk says cultivators can experiment with starting at a low intensity in this stage and increasing light gradually to better acclimate and prepare plants for more intensity in the vegetative and flower phases.

“We recommend 50 micromoles a day of increase in veg and about 100 micromoles a day in flower, but all of this is cultivar dependent. And I do like to emphasize that because cannabis genetics are so diverse,” Kirk says. “You have to be careful not to do it too fast because you can stress the plant and set yourself back and lower your yields. Some cannabis [cultivars] can handle a higher light intensity than others.”

4. Greenhouse growers must factor in DLI when increasing intensity.

Daily light integral, or DLI, is a measure of how much light plants have received within the entire photoperiod, and it is measured in moles per day. Greenhouse growers use this measurement to supplement cloudy days and account for the natural cycles of the sun.

“The plant doesn’t really care how the light is given, as long as that photoperiod isn’t interrupted too much and they are getting a certain amount of light required for growth,” Kirk says. “Indoor growers don’t focus on DLI as much because typically they will provide the same amount of light for the entire photoperiod.” (Although some growers use controls to mimic sunrises and sunsets, more research is needed to determine the efficacy of this approach, Kirk adds.)

Greenhouse growers need to factor in DLI when dialing up intensity. “If you have the same amount of light intensity given to the plant throughout that entire photo period, they’re going to get more light in veg than they are going to be getting in flower at the same light intensity” because the photoperiod is 12 hours in flower versus 18 in veg, he says. “We typically increase the light intensity day one of flower a little bit, and that way, we’re still decreasing DLI. Using an example here, say you’re leaving the veg room at 500 PPFD, you would need to start at 750 in flower.”

“All of this is cultivar dependent. And I do like to emphasize that because cannabis genetics are so diverse.”  —Taylor Kirk, horticulture service specialist, Fluence by OSRAM

5. For growers using tiers, veg time is important.

Growers can adjust the time plants spend in the vegetative phase to help control plant size. While cultivators using tiered systems can still increase intensity, they must be careful not to let the plants spend too long in that lifecycle stage, Kirk says..

“You want to keep smaller plants, otherwise they are going to outgrow the space that you provide them,” he says. “If you veg for too long, your plant is going to be pretty large when you initiate flowering and stretch even more. They always go through a growth spurt when the photoperiods change, so you need to keep plants shorter on a rack system.”

6. Consider growing environment parameters when adjusting light intensity.

When dialing up intensity, growers must account and control for other factors, like temperature, humidity, irrigation and nutrients.

“The last thing we want to do is to tell a grower to use light intensity that’s twice as much as they are historically used to using because we know we can get a lot more yield with that, but we’re going to cause that grower to fail if we don’t guide them through other factors that need to be adjusted, as well,” Kirk cautions. “There are many factors that need to be managed carefully when you push the plant in this way.”

The potential benefits are massive, as Kirk says growers can yield up to twice as much as commercial growers have historically yielded. That’s why he and the horticulture service team at Fluence spend so much time coaching growers through the process of increasing intensity.  

For example, vapor-pressure deficit, or VPD, is a metric they watch closely to be sure that intensity isn’t negatively impacting the relationship between temperature and humidity. He suggests keeping the VPD in the “less stressful” ranges of .9 to 1.3 kPa.

7. There’s a direct correlation between increasing intensity and the need for increased nutrients and water. Be sure to feed and irrigate plants more. 

Growing environment isn’t the only parameter that must be considered when adjusting light intensity, however.

 “The program that [growers] run, all the cultural practices, what kind of media they are using and fertilizer and concentration of fertilizer—all of these things need to be looked at if you’re thinking about increasing light intensity,” Kirk adds.

When growers provide the plant with more energy from light, they must supplement nutrients and water as well. However, each cultivar has different needs.

“I like to compare it to a bodybuilder. Normally, humans need probably 2,000 calories a day, and that’s your average diet, but if you’re a bodybuilder, you’re not going to be able to see the results that you’re after with 2,000 calories a day,” he says. “So you’re going to need to increase your concentration of calories and nutrients.” Kirk says the same goes for plants, as they need increased inputs when receiving more light.

Although the “meat, potatoes and vegetable” nutrients plants need like potassium, magnesium and calcium are key, nonessential plant nutrients also are important to help plants tolerate more intensity.

“Earlier research was done with soilless mix that had quite a bit of organic amendments and biostimulant additions. It wasn’t just fertilizer and water in a sterile environment [but also] the plant and microbial relationship as well, and there’s a lot of benefits in there that reduce stress,” Kirk says. “I definitely encourage the use of biostimulants.”

Amino acid and fulvic acid may be non-essential additives, for example, but they can be beneficial, especially when increasing intensity.

“If you’re really interested in pushing ultra-high light intensities to see this maximum yield potential from cannabis, you better be ready because everything that you’re doing impacts that performance and that yield potential,” he says. “It’s not just how much light you’re giving them.”