The Benefits of LEDs Vs Traditional Grow Lights with BlackDogLed

LEDs for Cannabis

LEDs (light emitting diodes) are now ready for prime time. The technology is mature and has incredible benefits. Listen in as experts Kevin Frender and Noah Miller of BlackDogLed.Com compare and contrast the benefits of LEDs versus traditional lighting. We provide details for both the business owner and growers. Learn more at

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Matthew: Hi. I'm Matthew Kind. Each week I'll take you behind the scenes and interview the insiders that are shaping the rapidly evolving legal marijuana industry. Learn more at What are the five disruptive trends that will shape the cannabis industry in the next five years? Find out with your free report at Now here is your program.

As cannabis prohibition ends, entrepreneurs are coming up with new and innovative ways to evolve the lighting of their plants. We have two entrepreneurs with us today to tell us how light emitting diodes or LEDs may replace conventional lighting. We are pleased to have Noah Miller and Kevin Frender from Black Dog LED of Boulder, Colorado on the show today. Welcome, guys.

Kevin: Hello.

Noah: Hello.

Matthew: Can you give us a little bit of background on yourselves, how you got into LED lighting and growing and this technology?

Noah: Yeah, this is Noah Miller. Hi, Matt. Basically, I had started myself, when I moved to Colorado about five years ago, did some work in the periphery of the industry and decided that I really thought there was a lot of promise and a good future. I chose to stay on the periphery versus the actual growing, but stumbled across Corey, who is the founder of Black Dog LED, who couldn't join us today, and at that point joined him and have been involved with Black Dog ever since.

Kevin: And I am Kevin Frender. I have been a plant nut basically my whole life. I have been growing plants under artificial lights for about 23 years now, mostly as a hobby and just playing around with a bunch of plants in my basement for a long time, trying to always find the best lights possible and tried out a number of LEDs, was very disappointed with them, until I tried my first Black Dog light and was so impressed with it that I actually quit my day job and came and joined Black Dog LED.

Matthew: I love it. That's faith, faith in LEDs. I want to get into some of the earlier, crappy LEDs. We'll dig into that in a minute, but for people that just have a very, very limited understanding of what LEDs are, can you just give a real high level overview of what LEDs are and their benefits. What people need to know, both a grower and a business owner?

Kevin: Sure. LEDs basically are electronics which are capable of producing light in a very different way from traditional lighting systems. Rather than getting something hot enough to the point where it actually starts glowing and producing light, LEDs work differently by actually using semiconductors to create light directly without the intermediate heat step. They are inherently more efficient than a lot of the traditional lighting sources out there. They also have a number of different advantages in that they actually produce light of specific wavelengths, so you can tune the spectrum of the light that you're getting out of it. That actually is a disadvantage if you're trying to create lighting for human purposes, because you want a broad light spectrum light to make things look normal for humans, but for plants, it's ideal. We can give them just the light colors that they really want.

Matthew: Yeah, that's something that became very clear to me when I dropped by your office. You were explaining that traditional lights, yes, they produce all this light, but a lot of it's not usable. It's kind of akin to the human hearing spectrum. It's like we can only hear in a certain spectrum of sound. Similar to light for plants, only a certain spectrum is usable. That was something that was very interesting to see. If you could describe in a few bullet points what's wrong with traditional grow lights, you touched on it a little bit. What's really the problem with traditional grow lights?

Kevin: Well, traditional lighting, what people use as grow lights, was actually designed for humans. It was not designed for growing plants. Someone just happened to notice that that streetlight they took down from their parking lot was able to grow plants, and so that's where traditional plant lighting comes from. The problem is that human eyes see primarily yellow light best. Our eyes are just inherently more sensitive to yellow light, so traditional lighting tends to really emphasize yellow light. Plants, unfortunately, don't want yellow light. They absorb a little bit of it and make use of a little bit of it, but they really want red and blue light and so traditional lighting has not been designed to create that because it's not useful for humans.

Matthew: I know on Ebay, and different places, there is a lot of LEDs that I would say are sub-optimal, to be kind. How do you steer away from sub-optimal LEDs and how do you know you're dealing with high quality LED?

Noah: That's a great question that we spend way too much time in this office on the phone with prospective customers discussing with them, why, just because they heard LEDs don't work, that's not necessarily the case. There are a few key things that we tell people to look at. One of the obvious ones is outrageous claims. You know the old saying, "If it's too good to be true, then it probably is," and in this case, we find that all the time. A good indicator is outrageous claims about wattage. For example, if they are selling a 400 or 500 watt LED and they say that it can perform or outperform 1,000 watt HID, that's just a flat out lie. Now someday we might be able to do that, but with today's technology, that's just a marketing claim that never holds water and it just doesn't hold true. Claims that are just outrageous are a good way to know you're dealing with a company that isn't really in it for the long haul and they're not standing behind their product.

Another thing to look at is time in business. There are a lot of companies that come in and out. In the four-plus years I've been with Black Dog, I can't even count how many companies we've seen come into the industry, the LED grow light industry, just to disappear six or eight months later, so looking a little bit into the history of the company, we recommend. Also, proven grows, if you can find well documented grows by either the company that's putting out the lights or their customers on YouTube or all the grow journals that are out there and the different forums around the web. Reputation, of course, plays into that and like Kevin was talking about, spectrum is key. We don't believe that lights that only use two, three, or four, maybe five different colors of LEDs are optimizing what you can do with LEDs and really taking advantage of the technology. Looking for a good, complex, often referred to as a full spectrum, is another indicator of the quality of the light you're getting, so it's those kinds of things.

We also spent a lot of time putting up an FAQ page on our site to help answer some of these questions and outline things they can look at and help demystify the LED, because a lot of marketing claims are just mystified marketing terms that really don't make any sense and so if you can cut through to the meat, that helps a lot.

Matthew: How do LEDs compare on heat cost and crop yields? I asked a lot of growers questions before the interview and those things come up a lot. What can you tell them about that?

Noah: Well, there is a huge advantage there. While we do say that one of the major advantages of LEDs is the spectrum, the advantage there, but heat is another major benefit. There are two benefits there. One, LEDs are more efficient at turning energy, the electricity you're putting in, into light instead of heat as Kevin described, the intermediary step in most traditional lighting, so you save heat there. Plus, in addition to that, we're going to be putting out some additional research that shows you actually need to and should be running a garden much warmer, about nine degrees warmer, than with HID traditional lighting. You can turn your thermostat up and anyone that's lived somewhere hot or tried to use AC to cool a building, if you can raise your thermostat a few degrees, in this case, nine, you can see some big savings there as well.

Matthew: Okay. Let's say I have a traditional grow operation with HPS lights. I purchase enough Black Dog LEDs to replace these lights. How long does it take to recover the cost with the additional savings that I have from the LEDs, on average?

Kevin: There are a lot of different variables involved there. It really depends on the size of your operation, your cooling needs, which has a lot to do with the ambient outdoor temperature, and seasonal variations thereof. There are a lot of variations, but typically, on the low end, it can only take six months in certain situations, and at the high end, within 18 months you will have paid off your investment in LEDs. Then you get to just keep reaping the benefits over time, not having to replace bulbs every six months, not having to replace reflectors, not having to pay the extra electrical bill for the cooling and creating the light in the first place. Plus you get a higher quality yield, a higher quality harvest, out of your lights.

Matthew: When you say "higher quality harvest," can you give some detail on what that means exactly?

Kevin: Absolutely. High pressure sodium bulbs, which are traditionally used for blooming cannabis, contain absolutely no ultraviolet light. In addition, because of the way they work, they unintentionally put off a huge spike of true infrared light, about 818 nanometers, which is well beyond the visible spectrum. It's well beyond the spectrum the plants can actually use and all it does is serve to heat up the plants. It's why, when you put your hand under a high pressure sodium light, it feels so darned warm. It's actually putting off more of that infrared light than it is any of the visible light, so most of the electricity is going into creating that extra heat. That heat is just stressing plants out and that's why you have to have massive air-conditioning units to keep flower rooms around, most people recommend, 75 degrees. Without that heat stress and with the ultraviolet light that we include in our LEDs, the plants are happier, healthier, and the ultraviolet stresses them in just the right way to produce natural sunscreens, which include CBD and THC so we typically see a 2% to 5% increase in CBD and THC concentrations when we test plants grown under our LEDs versus HPS lights, even the same strain.

Noah: And just to be clear, that 2% to 5% is the increase we're seeing at laboratory results, so it's actually up to 20% and such increase because we've tested cannabis side by side, same genetics, same grow medium, everything, and then had them laboratory blind tested again to see which light produced what, and we've seen increases from let's say 18% or 19% up to 23%. While 5% might not sound like a lot, we're talking a 20% jump in THC production in the same exact genetic.

Kevin: And in addition to the increase in the desirable chemicals in the yield, the flower buds tend to be a lot denser and tighter with our LEDs than they are with HPS.

Matthew: You talked a little bit about the color spectrum, the reds and the blues, and for someone that's never seen an LED grow light, it kind of looks like you're wearing those old-timey 3D glasses, everything is kind of red or blue. Can you talk about what the ratio is of red and blue light, and is it different from a vegetative to flower, or is it a consistent ideal color spectrum throughout?

Kevin: Yeah. We actually used to sell different veg and flower lights. The flower lights had more red in them compared to the blue. We did that because it's conventional wisdom on the internet that that's what plants actually need, cannabis specifically. You want blue light for vegetative growth and red light for flowering. The way that people came to that conclusion is because they had two choices, between a metal halide kind of bluish light and a high pressure sodium kind of reddish light. They found, rightfully so, that one works better for veg and the other works better for flower but that doesn't necessarily mean that that's what the plants actually want or need. After selling various different red and blue veg and flowering lights for a couple of years, we did enough experiments ourselves and enough research to show that if you have the proper combination of red and blue, the proper ratio for both life cycles, the same ratio works better than if you switch it in between veg and flower and we've done grow after grow demonstrating this. It actually cuts down on your time to your harvest, because the plant typically stresses out any time you change the color of light on it. It takes three to five days to get its footing, basically, again and adapt to that new light color. Without doing that and keeping the ideal ratio, we keep the plants more compact all the way through flower, which means they're expending less energy growing stems and more energy actually growing flower buds.

Matthew: Do you feel like that idea of keeping the spectrum consistent from veg to flower is finally penetrating, or is it still most people don't understand that?

Kevin: It really just depends on who you're talking to. The people that have grown with HID lights their entire lives will still argue that blue is better for veg and red is better for flower, and that is true when your only choices are between two technologies of HID lighting. Once you actually have the ability to fine tune the spectrum to whatever you want it to be, that LEDs actually gives us, then you can actually get beyond that and really discover, hey, one spectrum that's finely balanced works better for all life cycle stages. If you think about it, the sun doesn't change color between summer and fall. A lot of people think it does, but it actually changes color more between the morning and midday than it does between the seasons. Plants didn't evolve to get different colors of light at different stages in their life cycle. People have just come up with reasoning to explain what they're seeing in HID, even though it doesn't really match up with what plants actually want.

Matthew: Now you say lumens don't matter. Can you explain what lumens are and why they don't matter?

Kevin: Absolutely. Lumens area measure of luminous intensity weighted specifically for the efficacy of the light for human vision. Lumens are by far the best way of measuring a light and comparing two lights for purposes of illuminating areas that humans need to occupy. It is a measure of how well you're going to be able to see with that light. Now for plants we don't care about whether or not we can see the plants well, we just care about growing them well. It turns out that plants really don't like yellow light. In fact, the most efficient, in terms of lumens per watt, lighting technology out there is called low pressure sodium lighting. There is a reason you have never heard of anyone growing with a low pressure sodium bulb because it actually will not grow a plant at all. You put a plant under a low pressure sodium light and it'll be dead within a week but that's what gives you the most lumens per watt. Yet no one actually grows with them so that's just a good demonstration of why lumens are not important when actually comparing grow lights. They are a measurement intended for human use, not for plant use.

Matthew: Okay. You know, there's going to be a lot of growers listening and business owners that really like the promise of LEDs, and I think most people see it as inevitable. I think maybe one of the questions that's lingering is that, "Is this technology mature enough?" How can you assuage those fears so they understand that we are there now?

Noah: It's mostly a question of they need to either have somebody that's used the right LEDs, such as a Black Dog LED, or grow with it themselves. We often encourage... We have people calling in and asking about 50 or 60 lights and we say, "Look, make sure it's what you want and make sure it meets your expectations. Get one, get two, get three, and try them out. We stand behind the product and really the only way to really believe it is to see it yourself." That's one of the reasons we have the plant room that you saw when you came in, so they could even walk into our office and see what the lights are doing with plants in use. It's really a question of they need to try them to get a feel, or walk into somebody else's garden that's using them. The challenge, as we talked about before, is if they talk to somebody that maybe used an LED that was lower quality, they're going to hear it didn't work at all, and unfortunately, that might have been true for that light, but that does not hold true for the whole LED grow light industry. It's a question of trial and error at this point, I'd say.

Matthew: Okay, so let's say a grower does decide, "Hey, I'm ready to move into LEDs." Aside from changing out all their lights, what else do they need to do? Is there anything else?

Kevin: Well, there's really only two things we've actually noticed that are important to keep in mind when switching over to LEDs, and they're both related to the lack of infrared heat put off by the LEDs that HPS lights actually do put off. All of that extra heat that HPS lights put off mean that you have to run your air-conditioner more to keep the leaf surface temperature cooler, because it's important to understand that the ambient room temperature is not the same as the temperature of the leaves of the plants in the room. It's really the leaf temperature that's most important for considering the plant's metabolism, how fast it's going to grow. Just like with humans, plants have an ideal temperature range that they grow and metabolize best in. You need to actually increase the temperature in your grow room with our lights about nine degrees, as Noah said earlier, to get the same ideal leaf surface temperature and get that optimal growth rate out of your plants.

The second thing is because the soil isn't being hit with all of this infrared heat as well, the soil doesn't dry out as quickly. One of the things that often causes an issue there when moving to LEDs, if you're growing in soil, is that you're not having to water the plants as much, and that means you can't cycle through nutrients as much as you would want to with the plants. To get around that, we have discovered that using fabric pots not only create a better root system for the plant, but by allowing the soil to dry out on all sides, you can still flush through the nutrients in your plants at about the same schedule that you would with HID lighting in traditional plastic pots. We do recommend fabric pots for soil and then increasing your room temperature by about nine to 10 degrees.

Matthew: Kevin, you know a lot about growing, so I just want to ask, what do you think the ideal growing medium is in your mind?

Kevin: It really comes down to exactly what you're trying to grow, your style, what nutrients, your growing environment. I personally have had success with a number of different growing media over the years in different situations. It really just comes down to exactly what you're trying to do. I have had success with cocoa. I have had bad luck with cocoa. I have had great success with peat based mixes, as long as you have the right environment and you can dry out the soil in an appropriate rate. I have done hydroponics. I have used completely soilless mixes. Actually, one of my favorites is not really appropriate for cannabis use because it's way too expensive. It works very well, but for growing a plant that's only going to live three to four months, it doesn't make economic sense, but if you're going to grow a tree inside that you want to keep around for a decade, it's perfect, and that's something called arcelite, but again, I wouldn't recommend that for cannabis.

Matthew: Okay. I'm going to try something a little different here. I've had so many grower questions that I want to just kind of do a lightning round for Kevin and Noah to answer these kind of quickly. Here we go. How much better is a 5 watt diode in comparison to an HPS in terms of light intensity or saturation of light?

Kevin: So, there is a lot of different sizes of HPS lights out there, but when comparing with the 1,000 watt HPSs that most people run, 5 watt diodes have much better penetration. We typically see almost 24%, 25% better penetration, and more of that light that does penetrate is usable by the plants. In my own personal experience, I used to have plants under high pressure sodium and metal halide lights that I was struggling to keep healthy more than three feet tall. Now they are five feet tall under our LEDs and I've got a secondary layer of plants underneath them which is growing happily.

Matthew: Great. Is the LED strong enough to penetrate the canopy and/or reflect well off surrounding surfaces?

Kevin: Yes, absolutely. We always recommend reflective surfaces for any grow light. It doesn't matter what kind of grow light you're working with, if you have reflective surfaces around it, you're going to see an increase in the actual light hitting the plant.

Matthew: Are there better grow methods to use with LED, like "sea of green" so plants are small and LED can be kept close?

Kevin: So, technically "sea of green" is many small plants kept close together, although some people use that term to also describe plants that are just trained to be flat, so they'll use special trimming techniques to keep the plants more or less with an even canopy. Sea of green is very important if you're working with underpowered lights such as 1 watt or 3 watt based LEDs, because the light just does not penetrate very far into the canopy so having that very flat, very thin, even canopy is very important in that situation. It still works great with our 5 watt lights, but it's not as necessary to do that because we actually get the penetration power.

Matthew: What is the growth rate of a plant in comparison to an HPS or MH bulb for LEDs? How do LEDs compare to an HPS or MH in growth rate?

Kevin: Well, that's kind of a tricky question because it depends on what you're measuring as the growth rate. Plants will grow faster with the LEDs in terms of the number of leaves they're putting on, in terms of the number of flowers, but they're not going to grow as tall. If you're only measuring height, plants will grow less under LEDs, if you're only measuring height, but that's a good thing. You're expending less energy on growing stems and more on growing the things you actually want, the leaves and flowers.

Matthew: Great point. Let's say, I know you've done side by side comparisons, but let's say you've got a plant in veg and you put it under an MH bulb and you have one that you put under an LED. What's the difference going to be like one month later?

Kevin: So, the plants that were grown under metal halide are probably going to be a little bit taller and the plants that are grown under LED are going to be a little bit bushier and stouter. In terms of overall weight of the plants, they're probably going to be about equal. The difference is that more of the actual weight of the plant under the metal halide bulbs was going to be put into stems, whereas under LEDs it's going to be mostly leaves getting ready to absorb more energy and have a great flower.

Matthew: So, will the price of LEDs come down kind of how computer chips are coming down? Are they at the same rate or is it a little slower? I mean where do you see the cost in one or two years versus where they're at right now?

Noah: Overall we see the price staying stable and maybe even going up a bit, and then coming down. The reason for that is if you look at a technology, LED lighting technology in general is still fairly new, especially compared to how old HPS and metal halide are. In general what we see is a trickle down technology. As the technology improves and we can take advantage of it, we will, and that will keep costs up for a bit, but just like we're seeing now where you can buy a laptop for $500 or even less, which was unheard of years ago, and as the technology catches up and stabilizes, we do think costs will come down. That's probably a couple years out.

Matthew: If we can just review. What's the biggest benefit for a grower to switch to LED today?

Noah: For a grower, it would be healthier, more disease and pest resistant plants, easier to maintain, better take rates in terms of cloning and going from seed, just healthier plants all around. We see constantly people switching from HPS to LED and they take a plant they're used to growing for five or 10 years, they put it under LED, and suddenly the leaves are thicker, the stalks are healthier, everything is better in the plant and that just makes it easier for a grower all around in their day to day operations.

Matthew: And then how about for the business owner that may be on the fence? He likes the idea of LEDs but not totally sure.

Noah: Well, obviously as a business owner, what they're most concerned with is the profitability. The reduced operating costs of LED is unquestionable at this point. There is no doubt that it does reduce costs, as Kevin talked about. There is a payback period, a sort of an ROI on the LEDs of six to 18 months, but once you get beyond that, you're making more money than if you had gone with the HID solution. You have reduced operating costs also in terms of HVAC that we spoke about and then of course there is also the increased quality that we covered earlier where if you have a higher end product, you're going to be able to sell it for a higher price point. You have increased profit in terms of lower operational costs and increase in terms of your profitability, in terms of your costs of what you're able to charge for your product.

Matthew: Kevin and Noah, as we close, what's the best way for people to learn more about Black Dog LED?

Noah: The best way is probably our site. We spend a lot of time maintaining it and making sure it's up to date with current information, as LEDs do tend to change rather quickly. Like I mentioned, our FAQ page is a great educational page and we do have a blog, a knowledge center on our site where we're constantly releasing new information, new findings, new research that we're doing so the website is a great resource. To be honest, we love talking to customers. We spend probably about half of our day here talking on the phone and chatting with customers on our site. Everybody that answers the phone has to grow with our lights and we've added it up and we're about 100 years of growing experience between the guys answering the phone here, and/or gardening specific experience. Even if it's not lighting specific, we get people calling with weird diseases and questions about their garden and we're happy to answer those as well, because we do love what we do, so gardening is just part of the fun.

Matthew: Well, thanks so much to Kevin and Noah from Black Dog LED. We really appreciate you taking the time to educate us about the latest technologies in LED.

Kevin: Thank you.

Noah: Thank you.

Matthew: Thanks so much.

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