Light is enigmatic. It can change an entire scene, like the warm-blanket flick of the switch after a nightmare, or the sanctuary of a powerful torch when strolling down a gravel, country lane after sundown. Light is breathtaking and life-giving. And like the sacred terpene, light can communicate, in its own way. We can learn from it. I’ve spent about a dozen years of my life studying how light interacts with matter (spectroscopy), and the concept of the absorbance and transmittance of light. Color, for example, is rather illusionary, since what we see is reflected light off an object. A green shirt looks green since the fabric didn’t absorb those wavelengths of light. The blueness of the routine sky, or the redness of it at dusk. Again, light interacting with matter, scattering from particles in the atmosphere. And while some creatures, like a phantom anglerfish, or the uber-creepy Phronima, might thrive in the dark, the rest of us require light to live. Obviously, so do plants.
So, do plants want all wavelengths of light within the visible region of the electromagnetic spectrum, or just some of those wavelengths? What about ultraviolet (UV) or infrared (IR) light, aka radiation? While nature has perfected the symbiotic relationship between sunlight and photosynthesis, how does moving plants indoors affect lighting requirements?
I needed answers and so, I spoke with Noah Miller, the CEO of Black Dog LED. Noah, like many people in the cannabis industry, has been around cannabis throughout his life, although he thought (also, like many of us) that cannabis legalization would happen 20 or 30 years from now. So, when he rather randomly found himself in Colorado when history was being made through legalization in 2012, he knew he wanted to be involved. “As a tech guy, I felt that I missed out on the technological boom of Silicon Valley, since it was before my time,” Noah commented. “I knew I didn’t want to miss out on this revolutionary industry.”
So, he made his relocation to Colorado permanent, and joined in the once nascent movement sweeping across the state. After working in pharma, succeeding several years in natural products, Noah was happy to get back to what he was passionate about. “I started out as a trimmer in an underground grow,” he added. “You’ve got to wash dishes before you can be a chef. I ended up in plant care, which wasn’t a long-term play, but rather provided valuable hands-on experience.”
The fortuitous chronology continued, as one of Noah’s co-workers was taking a soil science class with the owner of a LED company. The two joined forces at Black Dog, a pathway Noah is still forging and refining as current CEO and owner. “We’re a trusted brand and haven’t gone out for the big money yet” Noah added. “I couldn’t be any happier for the path I chose.”
Respective histories related, I migrated to questions about the optimal wavelengths of light for growing cannabis. Are there specific lighting features that growers, whether novices or masters, should consider? “It’s no longer a question of ‘Do LEDs work for cannabis?’”, Noah responded. “Rather, it’s now ‘Who has the best product?’. If we remove all the garbage from Amazon, all the low-end products, and just focus on the top players, you’ll see that we are all buying the same dyes from the same companies. So, it’s how we design our light spectrum that differentiates us from our competitors.”
Black Dog focuses on two things: power and spectrum. “We make some of the most powerful lights in the world to strictly focus on cannabis, since it’s a high-light plant,” Noah provided. “Additionally, many companies put out basic white LEDs, likely since they’re easy to engineer, command the biggest sum of money, and because of all the past research and development, these LEDs are very efficient and are the cheapest to buy in bulk. These companies may toss in a red wavelength to enhance the flowering effect.”
“But we’re plant geeks at heart,” Noah continued. “Forget about dollars; we just wanted to design the best light for cannabis. We looked at the science to tell us what to design.” The result was an LED that uses nine discrete colors in the overall spectrum, although it looks slightly magenta to the human eye. “We also include UVA [ultraviolet] wavelengths,” Noah added. “Those LEDs cost 20x what our other LEDs cost, but I can prove to you through lab testing, done as a point of comparison against HPS lights [high-pressure sodium], that I’ll get more active compounds because we put UV in there. Plants put out sap to protect themselves, and therefore, you can produce more resin by dialing in the light spectrum used in cultivating your plants.”
Noah continued. “The benefit of using LEDs is not just the heat and power savings, but as plant fanatics, I can tell you that I can grow a stronger, healthier, more vibrant plant that puts out more flowers with our spectrum, rather than just putting out a light to grow the plant.” Noah pointed to lab testing Black Dog has commissioned that has shown terpene increases of 2-3% as a group.
Another study conducted by the Black Dog team considered optimizing ambient air temperatures used for cultivating plants grown under LEDs compared to other lighting. The experiment measured the surface temperature of the leaves of plants (including Cannabis) grown under eight different fixtures, including LED, HPS, fluorescent, and metal halide lights. Black Dog found that LEDs don’t heat plant leaves like the other lights. A plant grown at 75°F using HPS lights would require a temperature boost of approximately 9°F if using LEDs to produce the same optimal leaf surface temperature integral to plant metabolism.
The white paper discusses the fact that HPS, fluorescent, and MH lights “generate a significant amount of light wavelengths plants cannot efficiently utilize as an unintended byproduct of how they generate light. Unused light absorbed by a plant’s leaf will warm it up, affecting the ideal ambient growing air temperatures.” The study also reports that LEDs optimized for plant growth don’t produce excess infrared, yellow or green wavelengths like other artificial grow lights, including white LEDs. “Because leaves aren’t being directly warmed by these wavelengths that plants cannot use, plants grown under LED grow lights require warmer ambient air temperatures to achieve optimal metabolic rates,” the study reports.
There’s a lot more information on the Black Dog website, as Noah and his team are quite thirsty when it comes to scientific discovery and dissemination. “We do a lot of research,” Noah commented. “We’re just scratching the surface. As an example, we include some LEDs that other venders typically don’t, including a deep blue wavelength near 420 nm, which seems to give better penetration, and we believe it probably provides higher THC content. But we haven’t yet isolated the deep blue wavelength and ran a test batch isolating this wavelength when growing plants.”
I pointed out the cosmic forces likely at play, should a wavelength of 420 nm prove to be optimal for augmenting THC content. Time and science will tell. But in the spirit of venturing into the unknown, I asked Noah about organically produced LEDs (oLEDs), which are being explored in products like smartphones. Some of these oLEDs are being designed from terpenes. Might we, one day, witness cannabis plants grown using terpene-powered LEDs? “oLEDs produce the best blacks for TVs,” Noah replied, “so they make really nice screens. But they don’t yet have the power needed for growing cannabis. We make a 1,000-Watt light, and oLEDs just can’t compete with that.” I remain hopeful, though, as I’ve witnessed a small sampling of what the terpenes can do.
The wealth of information that Black Dog has provided to us is impressive. To date, they have added close to 100 educational growing videos on their YouTube channel. It’s dedication to the science and to sharing knowledge that makes Black Dog and every entity like them precious in our evolving industry. With 80+ years of catching up to do when it comes to R&D, we can’t sit around waiting for universities to get funded to conduct similar research. That is and will thankfully continue to happen, but given the glut of practical knowledge ready to be plucked from the plant, companies who evolve from just selling products to passionately dedicating resources to experimentation, and then sharing what they’ve unveiled with the rest of us help peel back the layers that the mysterious cannabis plant reveals, one by blessed one.