So yesterday, I stopped by my local hydro shop to pick up some supplies and ran into a guy who was just going on and on about his grow and how his plants can “kick anyone else’s ass.” *eyeroll* . I noticed that he was buying one of those Exhale CO2 packs, and I asked him if he thought they worked well, noting that they really only work if the temps in the grow space are very high.
His response was that he uses the CO2 packs because he uses LED lights that NEED to run at 85 degrees. I was somewhat baffled by his response, and asked what kind of LEDs he runs. He said Black Dog LEDs. Hmm.
I thought he was full of it, as I’d never heard anything about LEDs that would NEED to run that high. So when I got home I looked it up and sure enough, found this on the California Light Works homepage:
“What Is an Optimal Temperature For Indoor Growing With LEDs?
Temperature is a metabolic regulator in terrestrial plants. Basic rule, the hotter it is, the faster they grow. As the temperature / plant metabolism increases, plants require more water, CO2, oxygen (roots only), and nutrients in the correct ratios. The plant will only grow as fast as the weakest link. In other words, if any one of these input parameters is limiting, plant growth will slow regardless of the level of the remaining parameters.
78 degrees Fahrenheit (78F) is the widely accepted optimum temperature for most plants at atmospheric CO2 levels (360PPM). This number is actually misleading, because this recommendation is based on tests done with Sunlight or HID lighting, both of which have very high levels of Infrared light (IR).
When a leaf absorbs IR, it heats the leaf creating actual leaf temperatures of 5-7 degrees higher than the 78F degree air temperature. Thus with light sources rich in IR, an air temp of 78F is functionally 83F-85F to the plants metabolism. LED’s emit no IR, so to achieve similar metabolic rates found in HID or greenhouse conditions at 78F air temp,LED growers need to run the room air temp at 83F-85F. Air temp can also be lowered by 3F-5F in the last 2 weeks of flower to enhance ripening, but remember as relative humidity goes up the air temps go down, so be prepared to make adjustments accordingly.”
Source: https://news.californialightworks.com/tips-tricks-best-practices-for-growing-with-leds/
Granted, this article is from 2015. But it raises the question: do quantum board type LEDs solve the problem of needing to run high temps by supplementing enough IR?
Or is this just complete bull? They guy who told me this seemed like some kind of rainman type savant. Really socially awkward and tactless, but you could tell he knows his science.
His response was that he uses the CO2 packs because he uses LED lights that NEED to run at 85 degrees. I was somewhat baffled by his response, and asked what kind of LEDs he runs. He said Black Dog LEDs. Hmm.
I thought he was full of it, as I’d never heard anything about LEDs that would NEED to run that high. So when I got home I looked it up and sure enough, found this on the California Light Works homepage:
“What Is an Optimal Temperature For Indoor Growing With LEDs?
Temperature is a metabolic regulator in terrestrial plants. Basic rule, the hotter it is, the faster they grow. As the temperature / plant metabolism increases, plants require more water, CO2, oxygen (roots only), and nutrients in the correct ratios. The plant will only grow as fast as the weakest link. In other words, if any one of these input parameters is limiting, plant growth will slow regardless of the level of the remaining parameters.
78 degrees Fahrenheit (78F) is the widely accepted optimum temperature for most plants at atmospheric CO2 levels (360PPM). This number is actually misleading, because this recommendation is based on tests done with Sunlight or HID lighting, both of which have very high levels of Infrared light (IR).
When a leaf absorbs IR, it heats the leaf creating actual leaf temperatures of 5-7 degrees higher than the 78F degree air temperature. Thus with light sources rich in IR, an air temp of 78F is functionally 83F-85F to the plants metabolism. LED’s emit no IR, so to achieve similar metabolic rates found in HID or greenhouse conditions at 78F air temp,LED growers need to run the room air temp at 83F-85F. Air temp can also be lowered by 3F-5F in the last 2 weeks of flower to enhance ripening, but remember as relative humidity goes up the air temps go down, so be prepared to make adjustments accordingly.”
Source: https://news.californialightworks.com/tips-tricks-best-practices-for-growing-with-leds/
Granted, this article is from 2015. But it raises the question: do quantum board type LEDs solve the problem of needing to run high temps by supplementing enough IR?
Or is this just complete bull? They guy who told me this seemed like some kind of rainman type savant. Really socially awkward and tactless, but you could tell he knows his science.
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I expect the guy has a point, but I watch with interest. If the only difference the IR on the high end lights makes is leaf temperature, and the same result can be had by raising air temperature, my cheap DIY screw ins just got better, not that they did too badly last winter. 
