Converting from HPS to LED lighting can seem like a daunting task, but at Hawthorne Gardening Company, we take a holistic approach to understanding how the differences in technology affect your entire growing environment.
In this webinar Hawthorne professionals walk you through key adjustments that we’ve learned through rigorous testing in our R&D facilities and partnerships with elite growers to help make your transition to LED seamless.
This is a webinar recording from The Emerald Conference with MJBiz Daily moderated by Adam Rivera, Conference Content Programmer for MJBizCon.
Featuring
Webinar transcript.
An edited version of this webinar’s full transcript has been provided below for your convenience.
Adam Rivera — Hello, everybody and welcome. My name is Adam Rivera and I work as a conference content programmer for MJBiz, and I’ll be serving as your moderator for today’s webinar. First I’d like to thank today’s sponsor Hawthorne Gardening Company for today’s webinar, converting HPS to LED key considerations. In today’s webinar, Dr. Craig Yendrek, senior scientists with Hawthorne Gardening, Hai Truong, VP of sales, and Brandon Robinson, Technical Services Engineer at Hawthorne. Will discuss how Hawthorne Gardening Company takes a holistic approach to understanding how the differences in technology affect your entire growing environment, and walk you through key adjustments that they’ve learned through rigorous testing in their R&D facilities, and partnerships with the Elite Growers to help make the transition to LED seamless.
After the presentation, Craig, Brandon, and Hai will be available to answer questions from the audience. So please use the Q&A box below for questions. Those questions will be addressed by the group after the presentation. So let’s go ahead and get started. I have some questions here for you all. So we’ll go ahead and dive right into those. So how has Hawthorne gained knowledge of LED implementation?
Craig Yendrek — The short answer is that we’re actually running biology trials with our new LED fixtures. I’m Dr. Craig Yendrek, the lead biologist on the lighting and nutrient teams for Hawthorne, and Hawthorne’s a unique company because it’s one of the few that in the cannabis industry that has biological capabilities. Currently, we have a team of over 20 biologists working at one of our four field research stations, and we’re testing entire portfolio of Hawthorne products. One of those research stations that’s located in Kelowna British Columbia, Canada, and it’s operated in partnership with the Flowr corporation (since this webinar the Kelowna facility has been fully acquired by Hawthorne), licensed cannabis cultivator in Canada. For over a year now we’ve been running R&D trials in Kelowna. The facility has over 20,000 square feet dedicated to cannabis cultivation research, and the unique part about the Kelowna facilities it’s divided into 10 grow rooms.
Each one of those grow rooms can be controlled independently. So it creates really a specific research environment that we can custom our growing conditions, similar to commercial grower. We have rooms dedicated specifically for propagating our own plants. We have grow rooms outfitted with all the benching and fertigation infrastructure that allows us to grow as any commercial grower would. That allows us to conduct separate trials all at the same time, but individually focused on lighting or nutrients or growing media. And one of the key parameters for our success criteria is we have post harvest drawing and curing rooms that allows us to measure bud yield. We also have an onsite analytical lab that allows us to measure all the key aspects of plant chemistry.
This gives us the opportunity at our Kelowna facility to do trials with our own products, either commercially available or new experimental products, while mimicking the exact growing conditions in indoor growth facilities. We examine how our nutrients pair with different growing media substrates, how the application rates differ under various grow lights, and how growers can adjust their irrigation patterns to maximize crop performance. In other words, we can really study the entire connected system. Plus we’re not running trials in small reach and grow chambers like a university might do. We’re really putting ourselves in the same shoes as actual growers.
Brandon Robinson — On top of that with our R&D team, we also have a full technical services team that’s on the field technical group. It’s a team divided up into a mechanical portion and a horticulture portion. So we have a team of engineers who do lighting layouts, HVAC design, airflow layouts as well as horticulturalists who can help with fertigation, irrigation, different fertilizer mixes really help growers out if they’re having issues and support any of the products that we really are putting out there in the market.
Within Canada, we have the ability to do analytical services. We also have the ability for different horticultural services and different controlled environment services, whether that’d be HVAC or lighting or airflow irrigation. We really are a 360 degree team. Controlled environment agriculture is somewhat of a complex system and by having a team that has a background in every one of these categories, we’re able to look at every item within the grow, and really help growers maximize whatever they’re trying to accomplish.
Hai Truong — Let me add this piece also; at Gavita and Sun System, we’ve been testing early technology dating back 12, even 13 years ago. Early LED fixtures in the marketplace, lacked intensity, proper color spectrum, and reliability. What they didn’t lack was price, these things were going for four to five grand. We started noticing about three or four years ago, LEDs began to match or even surpass the performers and yield of HPS. Some of the LEDs out there today actually improve yield and quality all at about 25 to 40% less Watts versus HID so thank you.
A.R. — It’s great that you all approach the needs of a growth facility from so many different angles. Let me move on to question number two. Craig, you mentioned the Kelowna facility. Can you tell us more about the type of research that’s being conducted there?
C.Y. — One of the very first trials that we ran in our Kelowna facility was to compare cannabis growth, bud yield, potency of plants grown with either the Gavita 1000 watt HPS or our new top light LED fixture, the CT 1930e. For the goal, this trial was really to determine if it’d be possible for a grower to do a one-to-one swap when replacing the existing HPS technology with the new top light. The goal here is to do that without any loss in productivity. For the trial, we set up a replicated design. We used multiple grow rooms and that allowed us to for reform the necessary statistical analysis to make valid scientific conclusions.
For that, in each room we hung the fixtures at the same height and distance from each other based on an original lightning design that was optimized for HPS. And also in each room, we grew the same cultivar. We used the same substrate. We used the same continuous nutrient feed program with the same environmental set points for temperature, humidity, CO2 concentration. In addition, all plants were pruned the same way. All plants were dried and harvested the same way. The only key difference in this first trial was the type of lighting that was used.
H.T. — All this stuff very exciting. Some of the stuff I’m really looking forward to down the road is us digging deeper into customizing growing recipes based on genetics. Right now most growers are using similar or slightly modified recipes when it comes to feeding or lighting, environmental or even CO2. With Kelowna and other facilities, we expect to uncover some of the best practices that should revolutionize cultivation, indoor and outdoor.
A.R. — The next question is; what’s being observed in the two rooms?
C.Y. — We knew going in that there was going to be a difference in the amount of infrared radiation that’s emitted from these two different fixtures. The HPS spectrum has specific wavelengths in the region of electromagnetic spectrum that goes past where the 1930 emits, and that’s in the range of between 700, 850 nanometers. That infrared radiation that’s emitted from HPS has a tendency to directly heat the surface of the plant leaves. For part of the trial we monitored leaf temperatures to see how they might be different. These two rooms were set up using identical conditions that includes the identical ambient air temperature. So when we keep that ambient air constant, in this case we set it to at 26.5, which we optimized for the HPS room. What we actually found was the leaf temperature in the LED room was a few degrees lower. The room was divided into three different benches. We’ve got average temperature measurements that were collected from plants on each of those three benches in the 1930 room, also in the HPS room. You can clearly see there’s about a two to three degree temperature difference. It seems like it’s a minor difference, but it can actually have big effects on plant growth.
The key thing that want to emphasize here is that depending on what your current temperature targets are, when you do change to LED it could shift the temperatures of your grow operation below what’s optimum for cannabis. We really recommend new growers as you’re making that transition to go ahead, make an investment in an infrared thermometer to be able to measure the leaf temperature in your current HPS setup. Once you install the LEDs, you can make the necessary adjustments to your ambient air temperatures to achieve and match that desired leaf temperature that you were growing with before.
B.R. — Absolutely. With the change from HPS to LED, there’s the change of that leaf temperature. There’s a huge change to the entire environment. By changing the lighting technology, we’ve completely changed the way that heat is entering into the room and how power is being managed. An HID lamp is essentially a big tube of gas and we’re hitting it with high voltage. It’s exciting that gas it’s getting extremely hot up to, 600-700 degrees Celsius. All of that heat is being captured in that reflector and radiated down directly towards the plant, whereas with an LED the process is a lot different. An LED chip is three layers of semiconductor material, you apply electricity to it, it generates light and it also generates heat.
The difference is that instead of that heat being thrown down towards the plant, we have to manage the heat very differently, because LEDs don’t like heat, high heat temperatures on, on LED leads to very rapid degradation. So we need to pull that heat away from the LEDs as fast as possible. That’s why we have giant heat sinks on the back of LEDs because we’re quickly pulling that heat away from the LED, and we’re throwing it into the environment behind the LED rather than forward. So lots of heat is coming out the back of the fixture, with not as much heat coming out the front end, causing a large shift.
The thermal management of an LED fixture is one of the most critical design challenges. You can have an LED fixture for extremely cheap, but if they’ve overlooked the LED fixture’s thermal loads, that fixture is gone within a year. This is why with the CT 1930, our new two-top light fixture, we have a patented heat sync design that’s there to make sure that the fixture can deal with all the thermal loads, because not only is it dealing with the thermal loads for LEDs, which is difficult with this type of LED fixture, with a top light it’s even more difficult, because instead of taking all those LEDs and spreading it over a four by four frame like in some of our other rail style fixtures, we’ve taken all of that heat and we’ve jampacked it into a smaller area. So managing that heat is very, very critical, but our engineers have done an amazing job dealing with that and actually making this fixture one of the fixtures with the highest ambient temperature rating on the market.
A.R. — What else are you observing?
C.Y. — We also monitored PPFD and that’s short of photosynthetic photon flux density. That’s a measure of the light intensity in the region between 400 and 700 nanometers, which is called par. For these PPFD measurements, the associate in our Kelowna facility took the measurements at canopy level as the plants were growing. Throughout the grow trial we monitor those light levels based on selecting just a few plants on the bench to get a good average at the canopy level.
In the LED room, the CT 1930s are providing a more intense light at the canopy. That really is a key driver for plant growth in the indoor environment. What does that mean to a grower? What we saw in these trials is a pretty good increase in bud yield, and that makes sense based on the scientific literature. There’s a really well known positive correlation between light intensity and crop yield, and that’s exactly what we saw.
B.R. — Yeah, it was actually our internal lighting design team that did the designs for the Kelowna facility. What was really nice about these rooms was that the HPS layout was done well before the CT 1930 had been developed. So when we did the conversion to the CT 1930, it was very much how we envisioned a lot of growers going through this transition of having already laid out their HPS. Our Gavita HR 96 reflector, switching that fixture out and putting in the CT 1930. And as you can see from the graphs, I have a video here, our PPFD is slightly higher, and our uniformity is slightly better, pretty much the same, but on average, it’s usually a little bit better.
B.R. — One of the main reasons that Craig’s team might have also been noticing a lower PPFD level with the HPS fixtures is, HPS lamps degrade over time. With those HPS fixtures, they’ve probably already been running for a certain amount of time, so they’ve lost some of their total output. It’s something that we always like to make sure the growers are aware of and when they’re changing out to an LED fixture, are we comparing a five year old HPS fixture to a brand new LED fixture? There’s generally going to be a large increase in your total PPFD output.
This leads us to the optic that we have in our CT 1930. Our original fixture of the Gavita double ended 1000 watt fixture had our reflector, which is called the HR 96. It’s a very widespread optic, and it allows great overlap from one fixture to the next, so that we can get great uniformity at a variety of different PPFD levels. I can put in a low density of lights to hit maybe 600 PPFD and with high uniformity [Brandon’s audio briefly cuts out] high uniformity. The idea with the optic from the CT 1930 was to mimic that distribution so that when we make the change, nothing really changes in terms of the light levels and the distribution that you’re seeing. A lot of the other LED top lights that are out there, normally don’t have a secondary optic because normally they reduce a lot of the amount of light that comes through, so they just use a raw LED output, which is what you can see on the right there
A one-to-one swap like that can, generally, lead to a lot of hotspots within a grow if they’re not laid out properly. Our optic though, because it’s another one of the patented items on our fixture, only loses about two percent of the total light out through the optic, which is something that’s pretty much unheard of for optics for LED fixtures. The discussion of optics and layouts and things like that, it’s something we always make sure we push forward is that you always want to get a light plan done for your larger grow rooms. There are a lot of different optics and light types out there trying to follow a rule of thumb plan of a four by four or five by five might not compliment the fixture in the way it’s supposed to be utilized, and you might not get the plan that you’re hoping for.
This is an example that I like to put it together. So this is a par map, if you’ve seen a light plan before, you’re usually looking from the top down and you see the light levels at a specific level, this is looking at the light from a horizontal, so a cross section of the room. As you can see on the top, if we’re using one of the more spotlight style of fixtures, where you get a very high intensity in one particular area, it’s really hard to get a uniform distribution of that light across a large canopy. We get a lot of spotty light in between each fixture. Whereas with the widespread optics, doing a proper layout that’s done by a design team, we can get a very uniform distribution of light so that the plants are all seeing basically the same light level. This is why Hawthorne has a wide variety of HID and LED fixtures, because it depends on what the layout of your room is. We can always find the right fixture that’ll fit the application for your grow.
A.R. — Craig, you had mentioned that to raise leaf temperatures we could raise the ambient room temperatures. What effect would that have on the HVAC systems and would there be a significant savings?
B.R. — I can take that one. This is a question we deal with a lot with some of the growers when they’re making the change. There’s no doubt that, making the change from HPS to LED it’s a large reduction of the amount of heat that’s going into your room, but it’s a common misconception some people think LEDs produce no heat. They do, they produce a lot of heat. They just produce more light per watt than an HPS is. To get the same amount of light, I just need to use less heat to do so.
There is generally a reduction in the amount of HVAC used, but it’s not as simple as I have 20% less heat therefore I have 20% less HVAC. It’s a much more complicated balance. An HVAC system is designed to take care of the sensible heat load in a room to maintain a certain temperature. When we take away a 20% of the heat that’s now in that room, we make a large shift to how the HVAC system reacts. Craig had mentioned, we raised the room temperatures. So we have now less heat in the room and we’re running the room a little bit warmer. What this means is that now we’re running our HVAC system a little bit less. If we’re running our HVAC system less, we’re losing some of that dehumidification that comes from the mechanical cooling within HVAC system, and we tend to see one of the biggest issues is growers having relative humidity problems in their rooms because their HVAC system was not prepared for that shift.
Generally, we tend to see a lot of supplemental dehumidification going into these rooms to compensate. So there is a savings to HVAC, but there are some other factors that we have to consider that it’s not as big as a reduction as some people would hope. That’s why we always kind of, when you’re doing these changes from HPS to LED, you have to think beyond the lighting, think about your HVAC and bring your HVAC, whoever you’re contracted with for your HVAC systems to make sure that this change is going to be able to work with your current HVAC system, and seeing what you might need to do to supplement, to take care of these changes.
A.R. — Thank you for that, Brandon. A topic that gets brought up a lot is the change in spectrum between LED and HPS. Has there been any observed effects in your research? We’ll pass this over to Craig.
C.Y. — I mentioned earlier about the differences in direct heat coming off the fixtures that can impact the leaf temperature and that’s primarily due to the difference in spectrum. But when we look and overlay these two which this figure is showing right here, you can see clearly how different the spectrum are. And this is actually the radiation that the plants are seeing. And so the concept here that we’re talking about is generally referred to as light quality. We can call it spectrum just to simplify things, but really what we’re talking about is the spectrum that’s emitted from the fixture, it’s composed of many different wavelengths at different nanometers throughout the electromagnetic spectrum. And really the range that drive plant growth the most is between 400 and 700. And so this, what you’re seeing here is really a paragraph or a photosynthetically active radiation.
One of the biggest differences that you can clearly see is that on the CT 1930 side, there’s a huge peak in the blue part of the electromagnetic spectrum and that can or has been shown to play influence plant growth in a number of different ways. One of them is that blue light can cause stomata to open. So stomata are those little pores on the surface of the leaf that allow gas exchange to happen. Changing CO2 and water vapor from the air and the leaf. With blue light or more blue light stimulates that that’s the model to open more. You could potentially get an increase in water loss. That’s going to have a directive impact on your irrigation management strategies and humidity control. Blue light has been shown to influence plant height, and so there could be differences in a node length or total height of the plants.
And blue light’s been shown to increase blood THC levels. In this particular trial, we looked at a number of these parameters, including plant height and THC content. We didn’t see any differences, but we do want to caution people when you do begin to grow to pay attention to these parameters, because depending on the cultivar that you use for your growth, there’s known to be some differential sensitivities there. And so you could see the first time you switched some subtle differences in those aspects of black growth.
A.R. — We touched about it briefly, but I wanted to dive back into the topic of power savings with the conversion to LED.
B.R. — Power savings is definitely a massive part of the change from HPS to LED. A lot of the times, it’s one of the main drivers. We’re getting the same amount of light into a room while using 20% fewer watch to do it. This savings is really what allows us to make that LED fixture be a lot more affordable than when you’re looking at the original sticker price. We’re not only saving money from the power we’re consuming, but with a new build, your electrical infrastructure designed based on an LED spec rather than an HPS spec. HPS spec can also be a large savings. There’s fewer breakers, a smaller transformer, reduction of your total HVAC unit sizing. So there’s a lot of factors that play into the savings that you’ll see beyond just the amount of kilowatt hours that you’re going to use. The question is about power savings, but for me power savings really just translates to, how much money am I going to save? If I’m saving power, I’m spending less money.
We work with a company internally called Synergy. They do energy rebates for our growers to try to get the most money back from the power companies for these rebates. We’ve seen ROIs on LED fixtures. In this case, there was an example case from Canada, where the return on investment was just over a year. So when you start to really look at the full lifespan of a fixture, rather than the upfront cost, the LED fixture actually comes out cheaper for the most part, when you look at it from its total lifetime.
H.T. — That’s all huge information, Brandon, you should take a look at our CT 1930. It utilizes more 27% pure wattage, when you compare it against a 1000 watt HPS LED fixtures, those 1000 watts, they route them down. They utilize it closer to 1100 watts or 1,080, our 17 E operates closer to 40% less watts when you compare to that 1100 watt fixtures. Factor all that in, excuse me, with the HVAC savings, no lamp replacements, every six to 12 months, and the labor involved in that. It’s a no brainer when you’re designing a room to consider LEDs when you’re, retrofitting an old pictures out to consider LEDs. Those ROIs are great factors and you also factor in the increase in yields, increase in the quality of the flower. Again, a no brainer.
Brandon mentioned the rebates in Canada, same thing in the U.S. The U.S. is offering on average of about 25% across the country to reduce the strain on the power grids at the indoor cultivation sites are calling from. Again, we partnered with a company called Synergy based out of Seattle. They’re the industry leading authority on energy rebates. They help us consult. They help us simplify the process and really to maximize the potential rebates that these fixtures fund. You do have to have a fixture that is LED DLC listed. DLC stands for a Design Lighting Consortium. You could go on their website and check it out, but before planning any license facilities or retrofitting we ask that you contact us or Synergy to really give you an idea of what the potential rebates are, a quick look up for us and we can really find out for you. Synergy has also been helping growers land, huge, huge rebates on HVAC equipment. So not just LEDs, but a lot of hardware for your grow room in general.
A.R. — You’ve convinced me, I want LEDs now. But how do I choose which ones to buy? I think that’s the question now.
B.R. — There’s a lot of LED fixtures out there on the market and, like we had mentioned previously, there’s a lot to overcome from an engineering perspective to make sure that you have a fixture that is going to last you a long time. Internally, Hawthorne has a large team of R&D engineers, PhDs, electrical engineers, and mechanical engineers. On top of that, we have our technical services team who help support the R&D team. We take feedback from our sales people on the road and feed all of that information back to our categories and R&D teams to make sure that we develop a product that’s meets the demands of the customer. We also have a large of investments in testing equipment within our world headquarters in Vancouver, Washington with, FCC Isolation Chamber, goniophotometer, integrating sphere, and test ovens.
We do a lot of testing internally to make sure that our fixtures are going to stand the test of time. I originally come from the commercial lighting industry, office, lighting, home lighting, things like that. When I made the switch to horticulture lighting, one of the things that I really wanted to make sure people understood is that when we talk about lighting in a horticultural facility, this is not the same lighting we have at home. This is not lighting so that you can see lighting so that, you feel comfortable. These are pieces of production equipment. If my light goes off at home, I’m missing a light. I can’t see quite as well. If I lose a light in my grow that’s money directly out of my pocket. So when you invest in an LED, you really want to make sure that it’s engineered to a high spec and that you have a company behind it that’s going to back it up and support it. Because when those fixtures go down, you want them back up and running as soon as possible.
H.T. — Yeah. Let me add on Brandon. Those are all great points. Go online and you’ll go find cheap LED fixtures that promote themselves as 1000 watt replacements. They go for about $99 up to whatever the sky’s limit is. But the old saying is true, especially when it comes to horticulture LEDs; you get what you pay for. So please do your research. There are many brands and all different price range. You heard Brandon mentioned several times that the quality of the inputs make a huge difference. The heat management, the quality of the diodes, the drivers themselves, not over driving the diodes. We engineered all of our fixtures to not overdrive the dials, but also over driving them will achieve higher marketables for the lesser quality units, but down the road those degrade much quicker. They also lead to unwanted color shifts and premature intensity drops. So please do your research or contact us and we can walk you through it.
A.R. — This has been fantastic information. Is there anything else you guys would like to add?
C.Y. — I just want to emphasize that every grow operation’s different. We saw in our particular R&D trial an increase in yield in the LED room compared to HPS room. The magnitude of that increase is going to vary though, based on numerous factors. So there could be cult far differences, environmental conditions. What we’re seeing though is something that’s been pretty interesting to come out of the Kelowna facility is that the concentration of the fertigation solution seems to play a pretty large role. When we fertigate plants with a relatively less concentrated solution, we see a bit of a larger increase in yield difference between the two fixture types. To level set expectations, if you’re already optimized for all your inputs and aspects of production, you may not see a huge increase, but really all of the work that’s come out of the colonial facility so far, we’ve seen bud yield in the LED rooms that it’s always been as good or higher. So it’s super exciting results.
B.R. — Yeah. And I’d just like to add that; control environment agriculture. It’s a really complicated design process. One change can have a domino effect on every other factor in the room. We at Hawthorne, we really have a great depth of experience in this space. We have experience from the traditional growers. We have experience from horticulturalists, from engineers, from really every aspect. And we’re really here to help support growers to make sure that when we’re making a change, we’re really considering every factor and really are just there to support them in every step of the way.
H.T. — I’ll just close with this; Please feel free to reach out to our sales team. Brandon mentioned the tech services offering and/or Synergy. All together, the Hawthorne Gavita, Sun System, and Synergy websites are also a great place to get started. We appreciate everybody’s time. And thanks for stopping by.
A.R. — We’re going to be switching into the audience Q&A portion at this point. I’ll read out the first question and whoever wants to take that one can go ahead and jump in.
So how will switching to LED affect my feedings?
C.Y. — This is a tricky one. I just mentioned some of the observations that we’ve seen out of the Kelowna facility, but I think to piggyback up something earlier that Brandon said, this is going to really be tied to transpiration in any adjustments that need to be made based on just more or less water needs for the plant. And so I think it will be possible to adjust slightly.
A.R. — When conducting the LED trials, did you guys use different types of light in terms of different wattages or different companies?
C.Y. — For the trials that we discussed earlier, that I referred to at the beginning of the presentation, we were just testing the research question about HPS versus LED, and we used our signature Gavita products for that. So there’s the double ended 1000 watt HPS versus the Gavita CT 1930e top LED.
A.R. — Which trial cultivar did you run under the LEDs? What was the average THC, LED versus HPS?
C.Y. — The cultivar that was used was Black Cherry Punch 2, we do have a population on site. We originally got that source from a supplier up in Canada. All of our yields were between, 50 and 75 grams per plant, and THC levels for that cultivar can run between I think, 18 and 23%. We were right around 17 or 18% in this particular trial. We’re pretty pleased with the performance of the plants under both conditions. Really the main difference that we saw in our testing was with the bud yield.
A.R. — Are there more options to play with the spectrum presets that wouldn’t be possible to get with an HPS?
C.Y. — That’s actually one area that we’re really aggressively researching on the R&D side. A lot of the work that we’re doing now in the Kelowna facility is to customize the spectrum in ways that are unique and novel with the end goal of manipulating or having some desired effect on plant growth and development. I can’t share too much about those specifics of those, because there’s still underway, but there should be some pretty interesting and exciting things that can be done by being able to customize and deliver a more prescriptive spectrum as the plants are growing.
B.R. — Just to add onto that, there are fixtures in the market that are all a tune-able spectrum and you can do a million different things. We really want to make sure that if we are going to do that that it’s worth it. If you have a million different possibilities to run with a light, it’s one more factor that can cause an issue within your grow. So before anything is released into the market that we feel is worth it, there’s going to be extensive research done on it to make sure that it’s worth the additional change to make sure that it’s worthwhile.
A.R. — All right. Well, it looks like we’re out of questions at this time, but, I just want to thank Craig, Brandon, Hai, for taking the time to put forth this presentation today, and answer some questions for us all and provide this fantastic information regarding LEDs. And we also just want to thank Hawthorne for sponsoring today’s webinar and that wraps it up.
Learn more about converting from HPS to LED here ⟶
