WA State Grow & Show
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I am finally taking the plunge from MH and HPS to LED. What should I be looking for? I need to replace 6,000 watts to LED. 3- 10'x15' rooms.
Lighting: Solid State vs. LED
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About 35w per square foot if you go with mid grade fixtures between 2.6-2.8 PPE, 2.8-3.0+ PPE fixtures are ideal get better coverage for the same wattage (not to be confused w/ 3.14 PPE diodes that everyone likes to advertise in big bold letters everywhere). Dual peak blues, single peak red (not dual peak, that's just marketing nonsense, 660's are already dominant in the 640 range they just peak at 660). Stay away from any fixtures that have dedicated far red or 730nm diode you don't want those in your main fixture unless they can be turned all the way off in flower. Over 20ppfd worth of it starts reducing yield and terpenes. If you're on a budget get medic grow fold 8's or ez8's, use code mogotyou @ checkout and save an extra 10% on top of whatever sales they are having. If you want the best Mo's, Photontek pro series, Mammoth, or Fluence. There is nothing in the middle that's better than medic grow in any kind of measurable way. Stay away from aci/mars/sf/vivosun/Migro they are all red heavy between 45-55%+ you generally don't want more than 35-40% red and no more than 2% far red for maximum genetic expression, yield, thrichs, and terpenes indoors, and then stay far far away from them pretty much anything on Amazon/temu/AliExpress/TikTok shop.
Happyclouds
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Great info Mo thanks so much
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Deleted member 210
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Hey, you sound like you know your shit on lighting but I'll have to argue a bit on Far reds. I use far red booster bars at various times in a grow. I turn them on only after lights out for 15 min. Sometimes in veg if I have small plants I want to flip I give them 1 week only of 15 min at lights out. I'm also using in flower, after they stretch out from 5 weeks until finishing. I'm a bit of a light junky, I have deep red pucks, far red bars, Blue booster bars, a Green booster bar and 2 Black lights. No UV yet other than the small Black lights 10w along with 2 FC4000-EVO'sin a 5x5.Other than the Black I use them all, Black lights I've used for some pics...
I really know not about any of it but through playing with them I've grown some nice weed. Tell me your thoughts if you have time.
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Deleted member 210
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Depending on your location you may need to add heat to your space. I went from a 1000w hps to 600w led thinking I'd save a few bucks, With very little heat coming off the lights and drivers I had to add a 1250 w heater in one tent and 2 reptile lamps in my other75w & 150 w I use 1 or both depending on temps in my basement. I also get harder, tighter & sparklier buds now than I did with HPS so its a trade off.
I'm a light engineer lol, far red has it's usefulness but it's pretty much exactly what you described to try and shorten the dark period so you can run longer light on hours in flower by using it at the end of the day. In a main fixture dedicated far red has no purpose, you get plenty from the bleed over in the 660's and don't want more than about 20ppfd worth of it continuously in flower hitting your canopy, over that reduces yield, terpene percentages, and terpene complexity. There have been multiple multiple specific studies on this going back to the 2022 paper by a masters student out of the university of Tennessee, and has sense been duplicated and confirmed multiple times by independent labs and research groups. Using it at the end of the day or start of the day is not the same as hitting it the whole time the lights are on, and if you are going to play with it, it is better done with supplemental bars so it's not competing for power and effeciency of your main part spectrum which is what drives photosynthesis.
As far as UV goes, if your not using 365nm UVA, or 280-310UVB you're literally achieving nothing turning up the intensity of your main light doesn't do. UVA at 365nm helps with coloring and thrichome maturity, and to cancel our the negative effects of to much far red. UVB 280-310nm can help increase thrichomes and terpenes with some strains (not all strains most have no benifit, some have negative benifit, and a small percentage have a positive benefit). In order to get usefulness out of UVB you need to hit it with enough intensity to trigger the UVR8 response in the plants, to do that you need T10 or T12 florescents and you're generally only dosing them 30-90 minutes depending on the strength of the florescents you use mid light on cycle the last 3-4 weeks of flower.
Anytime
D
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I've seen some of those studies but none do what I have done with just 15 min at lights out. They either go overboard and use them all through the grow with or without full spectrum lights. Same as the Blues. I started this after reading about the Emmerson Effect. So I did the extending of hours through flower 12/12 - 12.5/11.5 - 11/13 - 14/10 using the Far reds at sun up and sun down but I didn't have anything to hold as a standard so nothing to compare them to. They finished I smoked them done deal. I do notice a big difference with just 15 min at lights out. Not going for the Emmerson effect just what it does to my plants and I like. Using the Reds at lights out can grow me some big fat healthy leaves but it stretches me out of space.
Nobody cares about leaves in flower we care about bud structure, density, thrichome density, terpene percentages, and node spacing all of which far red negatively effects. Unless you're trying to stretch a squat indica in veg, or run a longer photoperiod in flower on a 12-16 week sativa so you can get it done a week or two faster your just wasting electricity that can be better allocated elsewhere.
Run a control with 437nm and 450nm blue peaks, 20-25% total blue, 35-40% total red, less than 2% far red. Run it start to finish from veg through the end of flower, in flower hit the plants with 1000-1200ppfd. Then in a space next to it everything else the same except the lighting with all your extras run the same plants temps humidity everything.
Come back in 3-4 months and tell me which plants finished better, it won't be the ones you adding far red and UV and whatever else your doing, and I can almost promise you it won't be the plants grown with extra far red or uv that perform better. Also not sure what studies you've read but there are plenty that have dosed anywhere from 3-30% far red with all kinds of different controls and most of them done in the last decade have been done with full spectrum led. Go to Google scholar, academia edu, frontiers, research gate and just search for them there are dozens and dozens maybe more. You can take the advice or not, doesn't matter to me it's not my grow. But this is my daily life and what I do for work everyday, I've personally developed 4 record breaking balanced led fixtures going back to 2023 when I was the first one to crack 3.05ppe at the fixture level with only 37% total red, and have personally logged over 25k hours r and d. There is no scenario you've talked about that I haven't ran multiple times and that others have also and the results are the same every time compared to properly balanced setups. Honestly with your main lights your'd almost be better off pulling those far red supplemental bars out and hanging up some veg bars with no red at all in them and adding 200-300ppfd to the canopy with them, then reducing your main light to bring the total reaching the plants back down to 1000-1200. That would give you way better results then what you currently have going on.
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Deleted member 210
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This years crops using far reds as posted above, please tell me how I can improve using your methods above.
No one cares about leaf growth? Without leaves you can't grow big buds. Bigger the better as far as I'm concerned I want as much energy as they can absorb until I don't need them any longer.
Like I said, cut the far red, add in more blues at the end of flower after the stretch has stopped, and get back to me in 3-4 months and tell me which one performed better overall. The plants look good but they don't looks as good as they could if you were properly hitting all the secondary metabolites, pigments, and photoreceptors properly. By over using red in flower you are diverting energy away from reproductive parts of the plants aka the buds and putting it towards the leaves. Once the leaves have been formed you only need to keep them healthy, you don't need to keep them growing and expanding.
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Deleted member 210
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I don't use reds while lights are on, only at Lights out after week 5 in flower . Can you point me to a study where they only use Far reds for 15 min at lights out? I do use the Blue 450nm Tarantula booster bars in veg and in flower up to week 9, also Green 550nm it supposed enhance the spectrum's & helps light penetrate deeper through the canopy & leaf tissue so says their promo stuff. As I said I'm more trail and error than learning the technical aspects. I respect your opinions but I have over 34 years of indoor growing pot experience behind me. I may miss a point or 2 I'm old. 73 but still willing to learn.
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Deleted member 210
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I just did a google search with an Ai response
Use far red lights for 15 min at lights out only, what effect will that have on cannabis plants?
Reply
A 15-minute exposure to
far red (FR) light immediately after lights out will trick the cannabis plants into believing the dark period started earlier, which can accelerate the onset of the flowering stage and potentially shorten the overall time to harvest. This is known as the "end-of-day far-red" effect.
Mechanism: The Phytochrome System
Plants use a light-sensitive protein called phytochrome to sense light quality and duration.
- During the day, red light (around 660 nm) converts the inactive phytochrome form (Pr) to the active form (Pfr). Pfr signals the plant to be in an "active growth" state.
- At the end of the day, a natural sunset has more far red light, which, along with the darkness, causes the Pfr to slowly convert back to Pr, the "rest" state.
- By providing a 15-minute pulse of 730 nm FR light at lights out, you rapidly accelerate the conversion of Pfr to Pr, essentially giving the plant a stronger, faster "go to sleep" signal. This makes the plant perceive a longer night than it actually experienced, even if the total dark period remains the same.
Potential Effects on Cannabis Plants
The outcomes of this technique can vary by strain (cultivar-specific) but generally include:
- Accelerated Flowering: The primary goal of this technique is to induce flowering faster, potentially shortening the time to harvest by a few days to a week.
- Increased Cannabinoid Content: Some studies have shown that end-of-day FR treatments can elevate THC concentrations in high-THC varieties, with one study reporting a significant increase in total cannabinoid yield for a specific strain (Northern Lights).
- Enhanced Photosynthesis: When used in conjunction with full-spectrum light during the main light cycle, FR can increase the overall efficiency of photosynthesis (known as the Emerson effect), leading to faster growth rates.
- Stem Elongation: Far red light generally promotes stem and branch elongation, which is a "shade avoidance" response. While a short pulse at the end of the day may have less impact than continuous exposure, some increased vertical stretch might still be observed.
- Potential Trade-offs: Over-exposure to FR can lead to less dense buds, "lanky" plants, and potentially reduced levels of certain terpenes and antioxidants. The brief 15-minute pulse is generally considered an effective compromise to gain the benefits without these negative effects.
In short, in practice it doesn't do anything but let you manipulate how many dark hours you need to initiate flowering like I originally said, if you aren't using it to manipulate the dark period your just wasting electricity. The only studies that show an increase in anything besides plant elongation were flowered between 400-800ppfd which nobody in the real world runs, at those levels you aren't even coming close to photon saturation, amd the increases they see are generally.done under doses of 2-10 hours not 15 minutes and is a direct result of more photons not some magical 730nm wavelength. The same thing could've been achieved by adding more normal par. Perfect example of this if you read between the lines is the May 2015 study done by Tyson Peterswald. As far as specific studies on end of day I'm out in the field and on my cell today, I'll have to get them to you when I get home tomorrow I don't remember them right off the top of my head. Also take what AI tells you with a grain of salt, a lot of times it's just repeating what light manufactures claim on their website or what someone wrote on a forum and doesn't give you full context or the variables.
Far-Red Light Boosts THC In Some Cannabis Strains And Lowers Energy Use, Study Suggests
Far-red lights can improve yield and the quality of specific cannabis strains, and reduce energy costs and carbon emissions amid energy-intensive cannabis cultivation.
www.forbes.com
Does Supplemental Far-Red DECREASE Cannabis Yields? – Mammoth Lighting
Welcome back to our ongoing blog series, originally shared on Instagram. Today, we delve into the intriguing world of Far-Red Cannabis Research. Buckle up, as we uncover the latest findings that might raise some eyebrows regarding 𝐒𝐮𝐩𝐩𝐥𝐞𝐦𝐞𝐧𝐭𝐚𝐭𝐢𝐨𝐧. If you've been following us, you might recall...
mammothlighting.com
Frontiers | On the contrasting morphological response to far-red at high and low photon fluxes
Plants compete for sunlight and have evolved to perceive shade through both relative increases in the flux of far-red photons (FR; 700 to 750 nm) and decreas...
www.frontiersin.org
Some are specific to end of day, some for short amounts of time, some for a couple hours, some are not, pretty much all of them say regardless of amounts, timing, or length of treatment makes the plants stretch and makes smaller buds. Some call it specifically end of day, some call it far red, some refer to it as r/fr ratio. Some are done with decent controls some are not, but again regardless of treatment they all pretty much have the same findings. Most have a bunch of cited sources and other similar studies either linked throughout them or mentioned in the references. It's a a pretty deep rabbit hole, but once you've managed to make it through a couple dozen of them and you actually run controlled studies and experiments yourself and have a good baseline you'll see the same things everyone else who's ever actually studied and expierement with far red finds. There are a few strains that have positive effects to it sometimes but it is few and far between and you almost always sacrifice something in trade off for whatever the positive was.
There are also a lot of different people who have gone on different podcasts, or recorded talks or lectures on the use of lighting which alot of times includes far red, but I don't have those bookmarked, i tend to watch/listen to them once and just remember the information or am familiar with the work already in some other fashion.
D
Deleted member 210
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Hey thanks for all that, I skimmed through and most of what I saw was having Far reds on for longer duration. I'd never get through all of that and understand it all, I'm an old stoner and that's all far too technical for me. There was some literature I read that supported my belief about using far reds at the end of day only.Far-Red Light Boosts THC In Some Cannabis Strains And Lowers Energy Use, Study Suggests
Far-red lights can improve yield and the quality of specific cannabis strains, and reduce energy costs and carbon emissions amid energy-intensive cannabis cultivation.
Does Supplemental Far-Red DECREASE Cannabis Yields? – Mammoth Lighting
Welcome back to our ongoing blog series, originally shared on Instagram. Today, we delve into the intriguing world of Far-Red Cannabis Research. Buckle up, as we uncover the latest findings that might raise some eyebrows regarding 𝐒𝐮𝐩𝐩𝐥𝐞𝐦𝐞𝐧𝐭𝐚𝐭𝐢𝐨𝐧. If you've been following us, you might recall...mammothlighting.com
Frontiers | On the contrasting morphological response to far-red at high and low photon fluxes
Plants compete for sunlight and have evolved to perceive shade through both relative increases in the flux of far-red photons (FR; 700 to 750 nm) and decreas...
Some are specific to end of day, some for short amounts of time, some for a couple hours, some are not, pretty much all of them say regardless of amounts, timing, or length of treatment makes the plants stretch and makes smaller buds. Some call it specifically end of day, some call it far red, some refer to it as r/fr ratio. Some are done with decent controls some are not, but again regardless of treatment they all pretty much have the same findings. Most have a bunch of cited sources and other similar studies either linked throughout them or mentioned in the references. It's a a pretty deep rabbit hole, but once you've managed to make it through a couple dozen of them and you actually run controlled studies and experiments yourself and have a good baseline you'll see the same things everyone else who's ever actually studied and expierement with far red finds. There are a few strains that have positive effects to it sometimes but it is few and far between and you almost always sacrifice something in trade off for whatever the positive was.
There are also a lot of different people who have gone on different podcasts, or recorded talks or lectures on the use of lighting which alot of times includes far red, but I don't have those bookmarked, i tend to watch/listen to them once and just remember the information or am familiar with the work already in some other fashion.
I've run my reds with lights on once and my plants shot up far too much in over just 1 week. However using them intermittently we can" crop steer" to stretch segments if need be. I had one of my best harvest ever with weight, sparkle and looks on my last run using far reds at lights out for 15 min after they were 5 weeks in flower with my Blue booster bars on through the day with the rest of my lights including Green.
Over 2 lbs dried out of 4 pots. I used split pots 8 -2 gal cells in 4 autopots 2 pots had 1 runt in each but the other 2 pots with 4 plants grew equally and produced a lot of nice hard buds. I think with better dividers I wouldn't of had any runts My plants only vegged for 25 days before I accidentally, unknowingly flipped them at transplant.
That's all far reds should really be used for is getting plants to stretch when we want them too, it's probably the blues doing the majority of the work making them denser and more covered in thrichomes than it is anything else. Or better grow practices and overall control of other environmentals like temps, humidity, vpd, watering, and feeding habits. Alot of times we improve multiple things the more expierenced we get at something and it's hard to pinpoint where the improvement actually came from. Once you've got the stretch you want you can cut the far reds is all I was getting at with any of this as they've served their purpose and are no longer contributing anything useful if you have other lights you can make up the difference in par with more efficiently, with the caveat being unless you are specifically trying to manipulate the dark period to shave some time off of the flowering cycle. Also nothing wrong with a a 25day veg, we honestly generally aim for a 21-28 day veg when we run photos most of the time anyway, 25 days is right in that sweet spot.
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