LED and BUD QUALITY

[Cerathule]

Where are you reading this?

I also apologize for being sloppy, its of course Pr and Pfr, not Pf and Pfr.
Pr and Pfr is two states of the phytochrome receptor protein. When it processes photosynthesis it has to go thru both forms to complete the process and the creates sugar and O2 out of CO2 and H2O. Each form has its function in this process, it has to go thru both states to complete the chemical process. Having access to both red and far red means that this process get faster and more efficient (emmerson effect). But the phytochrome also does more than this, it also measures night and day (nightfall means Far red > red light) and if the plant is in the shade (again Far red > red). So its a bit unexact to say that the Pr completes process that limit stretch; this whole stretch thing is kind of a byproduct to how the plant does red light photosynthesis: Pr and Pfrs main function is this and not photosensing.

Here are some primers on this if you like.

https://bio.libretexts.org/Bookshelves/Introductory_and_General_Biology/Book:_General_Biology_(Boundless)/30:_Plant_Form_and_Physiology/30.18:_Plant_Sensory_Systems_and_Responses_-_The_Phytochrome_System_and_Red_Light_Response#:~:text=Exposure to red light converts,the inactive form (Pr).

photosystems I and II

photosystems I and II - pigment systems I and II, PSI and

www.botanydictionary.org

I'm sorry but the phytochrome photoreceptor family has nothing to do with the photosystems. The 2 photosystems are each comprised of around a hundred chlorophylls + some accessory pigments in order to harvest light energy, dissociate water to gather electrons in PSII, and use these at the end of PSI to make energy-rich primary compounds.
The phytochromes sense, and weigh, the light qualities at the red end of the spectrum and the plant react to this in a lot of ways. Photosynthesis is also largely, and multifoldly, affected by this, but it's not that the 2 phytochrome absorbtion spectras are the same, or deriven from the same, as the 2 photosystem ones. But these 2 do indeed share almost a similar max quantum-effect peak - at around 725-735 for PSI & Pfr and 660-680 for Pr and PSII.

 

[Cerathule]

I for one am not liking LED. Tossed the Mars fc-e4800 back in the box after 2 blooms. This hlg knock off quantum board nearly just killed some healthy plants too, so it might be getting tossed next.

Busted the old reliable Hortilux back out.

One thing to consider is plants leaves adapt to the spectrum and flux density they're exposed to and swift crude changes will be met with stress.
The HPS industry did alot to even reduce the low amount of blue to even less when they did know, only a tiny amount is needed for a photoreceptor response (1umol) and for photosynthesis cyan, green, yellow or red is better than blue, and causes also less surplus energy directly at the locale absorption site.
But I think the LED industry has come along way to use chips actually designed for human lighting and turn these gradually into a good plant light. Some just cheap out on the expensive 660 monos which are most-energy efficient in the long run though. With the prices of electricity on the rise, these may still be the best deal in the long run.

 

[Rocket Soul]

I'm sorry but the phytochrome photoreceptor family has nothing to do with the photosystems. The 2 photosystems are each comprised of around a hundred chlorophylls + some accessory pigments in order to harvest light energy, dissociate water to gather electrons in PSII, and use these at the end of PSI to make energy-rich primary compounds.
The phytochromes sense, and weigh, the light qualities at the red end of the spectrum and the plant react to this in a lot of ways. Photosynthesis is also largely, and multifoldly, affected by this, but it's not that the 2 phytochrome absorbtion spectras are the same, or deriven from the same, as the 2 photosystem ones. But these 2 do indeed share almost a similar max quantum-effect peak - at around 725-735 for PSI & Pfr and 660-680 for Pr and PSII.

Thank you for correcting me though i feel somewhat vindicated being part of team "its complicated", its hard to get it right, lol. My main point regarding far red still seems to stand though, some far red is beneficial to the plant, even in flowering. But i didnt quite catch the difference between photosystem I and II and the the two forms of the phytochrome so im grateful for someone clearing that out.

 

[Cerathule]

Thank you for correcting me though i feel somewhat vindicated being part of team "its complicated", its hard to get it right, lol. My main point regarding far red still seems to stand though, some far red is beneficial to the plant, even in flowering. But i didnt quite catch the difference between photosystem I and II and the the two forms of the phytochrome so im grateful for someone clearing that out.

Yeah I'm with you here there's just too much evidence from studies and basically the various different levels where photosynthesis and perception happens to just ignore this huge amount of evidence. Also some of this evidence arises from properties which are similar, even identical, to all landplants, even bacterias to some extent. Because based on the physical laws or biological organs whose genetics are evolutionairy hardconserved over a huge timeframe.
A professor like Bugbee wouldn't advocate it so loudly and invest so much time doing rigorous studies to give proof to some of the lost theories he did pick up from Emerson et al. The main problem is FR has so many effects on plants, and via multiple systems or properties, that it's really difficult to anticipate its effect and especially, in the context of an isolate study to disentangle an observable and connect it to its real rootcause. In that sense the setup of a study can really dictate its outcome and it would be flatout wrong to simply generalize this on a broader scope.

 

[LostTribe]

One thing to consider is plants leaves adapt to the spectrum and flux density they're exposed to and swift crude changes will be met with stress.
The HPS industry did alot to even reduce the low amount of blue to even less when they did know, only a tiny amount is needed for a photoreceptor response (1umol) and for photosynthesis cyan, green, yellow or red is better than blue, and causes also less surplus energy directly at the locale absorption site.
But I think the LED industry has come along way to use chips actually designed for human lighting and turn these gradually into a good plant light. Some just cheap out on the expensive 660 monos which are most-energy efficient in the long run though. With the prices of electricity on the rise, these may still be the best deal in the long run.

If your not running a commercial room filled with 10 lamps there is no reason to worry about electricity usage. Quality of bud and ease of growth are primary.

 

[Cerathule]

If your not running a commercial room filled with 10 lamps there is no reason to worry about electricity usage. Quality of bud and ease of growth are primary.

If you're running a commercial OPs you have so much more costs to consider, for the homegrower if he/she wants to save running costs, it's mostly possible via better lights.

 

[greyfader]

you will incur about 30% more electrical consumption using hps instead of led just to produce the same amount of par photons. and then approximately 60% more electricity to cool them so even at a small scale hps doesn't make sense anymore.

 

[CannaT]

You cant have led bud that has quality of HID or sun grown one.
In some way leds dont produce lots of sulphure compounds and alchocols that will give you more rounded and tick high as you will have with HIDs.
They are just different Led high always clearer and not so heavy like Hids.

No mather how this bud look it cant have aromatic quality of Sun or Hid.

If anybody ever have led grown bud that have hard smell on solvents like glue,alchocol,varnish...no one ever.
When I smell this I know its best of the best...if I dont smell those kind of smell in weed no mather on how it look its mids and that all.

I have now mixed hps led room and plants are crazy quality so its best to mix spectrums if I need to chose only one Hids are way to go.

and for you there are some who swear by science and research as if it were scripture. I would tell you that science only makes sense if you are a scientist all the time. If you start to believe in science without questioning it, then it is best not to do science.

 

[CannaT]

The same cutting 1st picture under Led board but still catch some HPS lightimg from side.

Second picture is HPS only.

Still I think that HPS smell stronger than Led grown again and again...led buds are always denser and have more resin than hids which have more water in them and have bigger volume at harvest then leds.

And about IR sun have around 1380w of ligh power at m2 and about 300-500w of IR depends on location.
So plants are adopted to IR if you see almost half of sun light is IR in nature.
Plants first time in history grow with very low invisible light spectrum with leds its all new.
Leds are good can do the thing good but for my personal smoke I will stick to hids.
I buyed some led lights and I use them cuz I have them in my personal grow. That is the last time I bought one.
Even at summer small 315 CMH will do the job better.I saw it these summer.

While led have much "better" spectrum its fucking artifical lighting sun created by humans.
Hps is much more closer to real sun indoors thats why plants under hids behave naturaly.

I also saw if plant is placed under led board and close to hps. It start to grow in direction of IR emited lamp like led dont exist.

 

[JKD]

I think most of us posting studies would be aware of the limitations of the scientific method.
They include (but are not limited to): Human bias and error; over-reliance on quantitative methods; lack of absolute certainty; limitations in scope; reductionism; insufficient consideration of context etc. It lends evidence toward hypotheses or theories rather than providing absolute proof.
Where there is the saying "One swallow doesn't make a summer", there should be something similar regarding studies.
Regarding replicating the sun - the closest you'll come is with solar simulators, not any grow light. These used to be xenon, but are now LED.
I also like a blended spectrum for personal grows, where energy efficiency is not important to me. If cost was not a limiting factor I would have a fully climate controlled grow room with an ETFE roof and LEDs that are controlled via DLI/PPFD.

 

[Crooked8]

You cant have led bud that has quality of HID or sun grown one.
In some way leds dont produce lots of sulphure compounds and alchocols that will give you more rounded and tick high as you will have with HIDs.
They are just different Led high always clearer and not so heavy like Hids.

No mather how this bud look it cant have aromatic quality of Sun or Hid.

If anybody ever have led grown bud that have hard smell on solvents like glue,alchocol,varnish...no one ever.
When I smell this I know its best of the best...if I dont smell those kind of smell in weed no mather on how it look its mids and that all.

I have now mixed hps led room and plants are crazy quality so its best to mix spectrums if I need to chose only one Hids are way to go.

and for you there are some who swear by science and research as if it were scripture. I would tell you that science only makes sense if you are a scientist all the time. If you start to believe in science without questioning it, then it is best not to do science.

I have to disagree. As someone who has converted in both personal and commercial spaces with the same exact strains terpenes not only seem not effected in a negative way but were experiencing more smell and flavor than ever. This is whats being reported by consumers who have been with us for a decade or more. Our White Truffle is extremely fragrant and flavorful in that glue/varnish/sulfur like compounds. Nothing seems lost in our conversion regardless of the Leds used. Thats my experience with respect.

 

[Rocket Soul]

I think this: bud quality under led, is somewhat strain dependant. Our Mandarine kush (or was it cookies?) cut did really poor, especially in summer. Low high, low smell, not sticky. Even with great environment it was meh.
We eventually got new cuts recently, Rainbow and Animal cake, and our last harvest was the best one ever; even better than our Amnesia haze cut which was superb under hps. Huge chunky buds, great high and smell, sticky buds, tricome rails on leaves and fan leaves, really anything within 3" of a bud. Open the bud and you have that shiny tricome look. This happened even under the straight white 3000k 80cri lights, with around 30w/square foot. With the right cut and skills you can defo get that perfect quality under led but theres a bit more work compared to hps.

 

[greyfader]

while i disagree with CannaT's opinion about quality of hps flowers vs led flowers, i think his observation about infrared is part of the puzzle.

infrared is part of the sun's spectral output and may be involved in signaling some internal processes.

infrared heats the surface that it hits and temperature is the second most powerful regulator of metabolism.

i am certainly seeing a better response using incandescent in conjunction with led.

like hps, incandescent produces infrared but not the sharp spike at 825-850nm. just a smooth curve up through the entire range without the intense spike. it may provide a more gentle way of supplying infrared.

i don't think a lot is needed. i'm using 924 watts of warm white 2700k led and 150 watts of incandescent in the form of 6 25-watt appliance bulbs spread evenly over the canopy. i realize that watts of electrical consumption don't really correlate to photons delivered but it does give me a relative reference tool to use comparing results.

i think i'll do some reading tonight about plants and infrared.

 

[CannaT]

I have to disagree. As someone who has converted in both personal and commercial spaces with the same exact strains terpenes not only seem not effected in a negative way but were experiencing more smell and flavor than ever. This is whats being reported by consumers who have been with us for a decade or more. Our White Truffle is extremely fragrant and flavorful in that glue/varnish/sulfur like compounds. Nothing seems lost in our conversion regardless of the Leds used. Thats my experience with respect.

Imagine grow that cutting under Hids.

It looks like we have the same expirience you grow many modern strains and all of them need to have that smell very pronaunced. And you mention only 1 cuttings of all you run.
I say many times terpenes with leds are more pronounced or better to say more plant have more of them.
Led lights produce very low amount of stress and no stress no sulphure compounds.
Less sulphure compounds less smell of weed.

Will soon have Bruce Banger Led vs Hid same nutes,same soil,same day of planting.
Led smell atm more fruty various tones of fruit and kushy.
Hids atm have that smell maybe bit mixed up not so prounounced like led.
But with kind like peppery kerosine back that with led again is missing.

I dont know I run many cuts for years but never had that solvents smell with leds.
And plants are grown very good.
In good condiotions...Even when I give cuttings to friends who grow them under leds and hids its the same in my expirience leds dont produce them or produce them in very small amounts.

Also I have to take in account that I didnt grow under exact model of leds you grow.
Maybe its possible with them Idk...but tried many bought,DIY,they can produce good buds but great Im still waiting that.
I think after all this years of smoking not strain dependent If I dont smell hard solvents its not the best grown.
Even Jack Herer when its 100 dialed under Hids have bit of that Varnish smell.
And under lumatek led 100 dialed in still dont have it but have smell of buds like mushrooms that I have not expirienced never with Hids.

Led preserve more terpenes 100%
But have very small amount of SC,Alchocols...etc
All this is caused by small stress and less water evaporation.

While in conditions of high light stress due to high ratio of IR and high water loss plant will lose some terps and produce great amount of SC,Alch...

Thats the way it is thats why you only smell that on only one cut and in reality you need to smell that on every cut you grow.

 

[CannaT]

Jack Herer left Hids right Leds.

 

[Crooked8]

Imagine grow that cutting under Hids.

It looks like we have the same expirience you grow many modern strains and all of them need to have that smell very pronaunced. And you mention only 1 cuttings of all you run.
I say many times terpenes with leds are more pronounced or better to say more plant have more of them.
Led lights produce very low amount of stress and no stress no sulphure compounds.
Less sulphure compounds less smell of weed.

Will soon have Bruce Banger Led vs Hid same nutes,same soil,same day of planting.
Led smell atm more fruty various tones of fruit and kushy.
Hids atm have that smell maybe bit mixed up not so prounounced like led.
But with kind like peppery kerosine back that with led again is missing.

I dont know I run many cuts for years but never had that solvents smell with leds.
And plants are grown very good.
In good condiotions...Even when I give cuttings to friends who grow them under leds and hids its the same in my expirience leds dont produce them or produce them in very small amounts.

Also I have to take in account that I didnt grow under exact model of leds you grow.
Maybe its possible with them Idk...but tried many bought,DIY,they can produce good buds but great Im still waiting that.
I think after all this years of smoking not strain dependent If I dont smell hard solvents its not the best grown.
Even Jack Herer when its 100 dialed under Hids have bit of that Varnish smell.
And under lumatek led 100 dialed in still dont have it but have smell of buds like mushrooms that I have not expirienced never with Hids.

Led preserve more terpenes 100%
But have very small amount of SC,Alchocols...etc
All this is caused by small stress and less water evaporation.

While in conditions of high light stress due to high ratio of IR and high water loss plant will lose some terps and produce great amount of SC,Alch...

Thats the way it is thats why you only smell that on only one cut and in reality you need to smell that on every cut you grow.

Maybe I didnt articulate my point well. Having grown commercially and personally under HIDS(10+ years) and under leds with strains ive run for 13+ years I am seeing more terps/flavor than ever under Led. Multiple strains that ive held for a long time that I have experience both with Hid and Led growth. So both modern and classic strains like our OGs and my beloved Karma/Hortilab tester ive run for 13+ years are universally showing better in both terps and morphology under Led than they did prior under Hps/Hids. I used the White Truffle as an example because of the specific terps you mentioned “glue/varnish”. Led takes getting used to and dialing which I understand is a headache to adapt to. Weve certainly overcome some challenges and poor results in the past. But when all parameters are correct, Led should outperform Led in every sense including flavor/smell/terps. We are adding more light in the same space for less wattage, some folks can handle it and some have more trouble.

 

[Ca++]

Visually, I would take that bud on the right, every time.

I'm not so sure LED does give the plant an easier time. Looking at peoples adoption attempts, it seems the subject of VPD came into existence for home growers, just because of LED. While the blue is stressful. Lowering yield in many papers, while triggering protection responses, which are ultimately more smells.

The extra environmental demand could be viewed as a separate issue, that can be corrected without touching the lights. However, the HID plants, as baked as they were, were easier to look after. So LED has that butterfly effect of causing stress for the plant.

Its a bit inexact to say that the Pr completes process that limit stretch; this whole stretch thing is kind of a byproduct to how the plant does red light photosynthesis

Indeed. Nobody can be exact either. It's right at the forefront of our understanding, and so more of an idea than sound fact. You align with the idea though. Observation has shown a link between FR and stretch, but biology shows links not to stretch, but to other things. Biology shows blue linked to processes around stretch. The red stuff, is just interference, is all we can show. Observation shows some flowers totally ignore the Pr when blue is sufficient (80umol in one paper) while I have seen flowers where Pf accounted for just over 50% of the stretch response. So it's not clean cut. Nor are they cannabis, which is said to follow the first example.


Thank you for talking this through with me. It's been helpful. Perhaps you got little from it, as you like delving right to the depths it seems, but I'm happy to just find some direction. Ultimately, I know the big three in cannabis greenhouse lighting have already run these tests, and even if they are not sharing what their respective universities and greenhouse studies found, it is still clear what opinion they have formed, regarding the use of FR in the main lights. I was going to trust them, and hoped sharing their thoughts, while questioning the topic in general, might ease others into the comfort zone of truly professional lighting choices. Perhaps more papers will land soon, or I will stumble back upon the one's people have asked for. I don't really embrace this depth of conversation though, as I'm really just about practical application. So I can't move to surrounding topics, unless they to have a practical reason to of looked at them. Even then, they won't be bookmarked.

@Crooked8 is the Bugbee course as deep as some of these guys are going, or more focused on practical application, as I hope it is. I really don't feel the need to look at the mechanisms behind chlorophyll production, but do appreciate the need to fuel them. I'm unsure how deep to delve prior to the course, in order to keep up.

 

[Crooked8]

Visually, I would take that bud on the right, every time.

I'm not so sure LED does give the plant an easier time. Looking at peoples adoption attempts, it seems the subject of VPD came into existence for home growers, just because of LED. While the blue is stressful. Lowering yield in many papers, while triggering protection responses, which are ultimately more smells.

The extra environmental demand could be viewed as a separate issue, that can be corrected without touching the lights. However, the HID plants, as baked as they were, were easier to look after. So LED has that butterfly effect of causing stress for the plant.



Indeed. Nobody can be exact either. It's right at the forefront of our understanding, and so more of an idea than sound fact. You align with the idea though. Observation has shown a link between FR and stretch, but biology shows links not to stretch, but to other things. Biology shows blue linked to processes around stretch. The red stuff, is just interference, is all we can show. Observation shows some flowers totally ignore the Pr when blue is sufficient (80umol in one paper) while I have seen flowers where Pf accounted for just over 50% of the stretch response. So it's not clean cut. Nor are they cannabis, which is said to follow the first example.


Thank you for talking this through with me. It's been helpful. Perhaps you got little from it, as you like delving right to the depths it seems, but I'm happy to just find some direction. Ultimately, I know the big three in cannabis greenhouse lighting have already run these tests, and even if they are not sharing what their respective universities and greenhouse studies found, it is still clear what opinion they have formed, regarding the use of FR in the main lights. I was going to trust them, and hoped sharing their thoughts, while questioning the topic in general, might ease others into the comfort zone of truly professional lighting choices. Perhaps more papers will land soon, or I will stumble back upon the one's people have asked for. I don't really embrace this depth of conversation though, as I'm really just about practical application. So I can't move to surrounding topics, unless they to have a practical reason to of looked at them. Even then, they won't be bookmarked.

@Crooked8 is the Bugbee course as deep as some of these guys are going, or more focused on practical application, as I hope it is. I really don't feel the need to look at the mechanisms behind chlorophyll production, but do appreciate the need to fuel them. I'm unsure how deep to delve prior to the course, in order to keep up.

I also appreciate the bud on the right more! Way nicer morphology imo and Im nearly certain it would sell faster.

I am arguing that Leds give plants a harder time, not easier. We are adding more intense light than we had under HID in a given space. This takes our single most important cardinal parameter and demands more from the plants, which is why people struggle, they dont know how to keep up or i guess match up to what is required. I also rarely if ever heard of people watching their VPD prior to Leds. I certainly never really thought about it anywhere near like we do now. I just knew i wanted rh lower at the end of the cycle to avoid fungal pressure and increase trichome population etc. Although, they have been aware and focused on VPD in nearly every other form of agriculture on commercial level according to Señor Bugbee.

As for their course. I cant recommend it to YOU enough. You specifically, because I feel you have a terrific grasp of the science and a mind thats seemingly willing to listen. They go somewhat deep in almost every section but in the most practical way imaginable. If they open up the course again, please do it, I would value our back and forth with it and I think you would also submit great questions to Bugbee and his team that they will probably cover in following modules they release.

 

[greyfader]

@CannaT i grew with hps for 22 years before i used leds. i have been using leds for 5 years. i can say that i'm growing much better quality now with leds than i did with hps.

higher cannabinoid and terpene profiles, very sticky, dank flowers.

this isn't magic. there have to be sound reasons why leds are becoming more popular and hps are becoming obsolete.

has it occurred to you that if you are not getting the quality you want from leds maybe you don't understand them yet? maybe you haven't learned how to use them yet to get the results you want?

i'm not trying to be rude. i respect your intelligence, but you are making statements that are very subjective in nature without offering evidence.

you say hps is superior but cannot say why.

when i switched to leds from hps there was a learning curve. it took me a little while to get used to them.

i've included a couple of pics from my facility in oregon. these are sunlight supply ac/de fixtures with philips greenpower DE bulbs. these were the best on the market at the time i bought them. i had 49 lights.

also, i was in a legal environment growing for extraction and the law required me to lab test everything.

so, i knew exactly what i was producing and it was very good. 65-70 different strains over a 5 year period.

so, i know good weed from bad weed and i know i'm growing a higher quality product right now with leds than i ever did with hps. and i'm using stupid home made lights.

you compare the sun and hps as if they are close in spectral output but in reality leds have a more complete sun-like spectrum.

you say that you get sulphur and solvent smells but that it is at the cost of terpenes.

i can't sell weed where i live that isn't terpene-loaded. the market is much more sophisticated than it used to be. it has to have a strong psychoactive effect as well or i can't sell it.

there's nothing inherently wrong with leds that makes hps automatically superior. it's how the plants are cultured.

 

[greyfader]

I also appreciate the bud on the right more! Way nicer morphology imo and Im nearly certain it would sell faster.

I am arguing that Leds give plants a harder time, not easier. We are adding more intense light than we had under HID in a given space. This takes our single most important cardinal parameter and demands more from the plants, which is why people struggle, they dont know how to keep up or i guess match up to what is required. I also rarely if ever heard of people watching their VPD prior to Leds. I certainly never really thought about it anywhere near like we do now. I just knew i wanted rh lower at the end of the cycle to avoid fungal pressure and increase trichome population etc. Although, they have been aware and focused on VPD in nearly every other form of agriculture on commercial level according to Señor Bugbee.

As for their course. I cant recommend it to YOU enough. You specifically, because I feel you have a terrific grasp of the science and a mind thats seemingly willing to listen. They go somewhat deep in almost every section but in the most practical way imaginable. If they open up the course again, please do it, I would value our back and forth with it and I think you would also submit great questions to Bugbee and his team that they will probably cover in following modules they release.

i think one factor that i overlooked initially when switching to leds is that led lighting drives the plant at a higher metabolic rate at any given wattage.

then i realized that it is because led fixtures are mult-point instead of single-point emitters. plants under muti-point lights simply have less shaded surface than a single point source. less shaded surface equates to a higher metabolic rate.