LED and BUD QUALITY

[Rocket Soul]

Agrobar has the most blue of the lights ive used which is why i seem to get better morphology out of them. As for UV, is the jury not still out on that regarding terps? I know in bugbees trials with UV there was no correlation with any cannabinoid content increase in any UV spectrum. Im not saying i couldnt benefit, maybe i could. But having used HPS and CMH for decades you couldnt pay me to go back. Strains ive had for 14 years are showing better in literally every department under agrobars specifically. I tried several other led brands with some great and some not so great results. However, as we all know we are all always learning and I have way more experience with Leds now than ever. I still have a hand in a smaller grow that a friend runs with half cmh 315s and half leds. I see the results from both consistently. Leds there are also always showing higher quality and denser product with better stacking. And he runs Boulderlamp Leds not Agrobar, still way better terps/ice/morphology.

From bugbee

"Cannabinoid concentration in the lowest UV treatment was about 15% higher than the control in rep one and 10% higher in rep two, but the effect was not statistically significant."

What does this mean? That yes, in their experiment the average for cannabinoides was 15% higher in the uv condition but the variance of their measurements meant a large standard deviation which meant they could not arrive at a certainty of 95% that the higher level of thc was down to the experimental condition and not thru randomness. But he did infact measure higher thc in the lowest uv condition by 15 %, over no uv.

People seems to entirely miss out on this, he doesn't say uv has no effect, he says his statisical analysis does not support that the higher thc in his experiment is due to the uv conditions of his experiment (there are plenty of reasons of why this could be that i wont go into here)

For any normal scientist this (measured effect but no statistic significance) would mean "study this more" not "we have concluded theres nothing here" especially when there is so much, both in studies/papers and 1000 of years of anecdotal (growing in elevation will make the stone more intense) saying uv does affect potency.

I really find it quite strange to see so many latch onto this guys science. Why would it be more important than any of the papers saying uv does affect thc and quality? I suspect its down to collective lazyness: just like CannaT only presenting a header or blurb of a study with a basic summary people tend to not try to read and understand the nitty gritty details of these papers. Most people walk away from reading that paper thinking "so nothing happened" rather than "he measured 15% more cannabinoides but couldnt prove it was because of the uv to a 95% certainty" which is the actual real take away from this study.
Also Bugbee presenting his findings on youtube makes people believe him over other papers and scientist. i think hes on youtube this in order to sell his parmeters (hes behind apogee).

Its so easy to test for yourself. Just throw some uv leds over a tray. Grow out one of each of your genetics and get some friends to do a blind test after dry and 2 months cure on the stick. Its easy to tell a difference for anyone.

 

[mm4n]

"Cannabinoid concentration in the lowest UV treatment was about 15% higher than the control in rep one and 10% higher in rep two, but the effect was not statistically significant."

What does this mean?

I am not familiar with the methods of the cited study, but perhaps what Bugbee means is that the measured variation is statistically irrelevant because it is the percentage of a percentage: an increase of 10% in THC in a strain with 20% brings it to 22%, which is less (2%) than the variation often found when analyzing different buds of the same plant.

 

[Rocket Soul]

Agrobar has the most blue of the lights ive used which is why i seem to get better morphology out of them. As for UV, is the jury not still out on that regarding terps? I know in bugbees trials with UV there was no correlation with any cannabinoid content increase in any UV spectrum. Im not saying i couldnt benefit, maybe i could. But having used HPS and CMH for decades you couldnt pay me to go back. Strains ive had for 14 years are showing better in literally every department under agrobars specifically. I tried several other led brands with some great and some not so great results. However, as we all know we are all always learning and I have way more experience with Leds now than ever. I still have a hand in a smaller grow that a friend runs with half cmh 315s and half leds. I see the results from both consistently. Leds there are also always showing higher quality and denser product with better stacking. And he runs Boulderlamp Leds not Agrobar, still way better terps/ice/morphology.

Boulderlamp has one fixture with near UV (405nm so actually really violet), their sb2 light with something they call cycling beam (not sure what they mean) this would be a very good start at uv supplementation though weve had better results when pushing a uv supplement with continuous coverage from 400 down to 365nm

 

[Rocket Soul]

I am not familiar with the methods of the cited study, but perhaps what Bugbee means is that the measured variation is statistically irrelevant because it is the percentage of a percentage: an increase of 10% in THC in a strain with 20% brings it to 22%, which is less (2%) than the variation often found when analyzing different buds of the same plant.

Youre half right, hes not saying thc went from 20% to 35%, it would have been from 20 to 23. I understand what youre saying about variability within a plant, when you take samples you will always have variance within the same gauss distribution (this thing im sure youve all seen some time).

When you do comparative studies like this you apply some statistics tests to your results, in this case its called the T-test. It basicly examines the mean of your two test conditions together with variance and standard deviation in order to evaluat the probability if your results are all from the same gauss distribuition (and the difference is down to chance and fluke) or if they are actually two diffent sets of distributions, like this:

Generally in order to say: we saw a difference between the two conditions you need to have a 95% certainty.
The lower the variance in the results and the more samples the easier this gets. The less samples and more variance the harder it gets to show that the difference in results is actually down to the experiment and not flukes.
This is the way most science works, we never get a 100% certainty only a 95% that the higher thc values in the UV condition are actually higher because of the uv and not due to some random flukes that made us get the strongest buds on one side and the weakests on the other. Bugbee found effect (higher thc) but since his numbers were a bit all over the place he couldnt say with 95% certainty that the effect was due to uv.

However and this is very important to understand: he does not prove that uv has no effect on cannabis. He shows that the his experiment was not able to attribute the increase in thc to the uv condition. Thats ALL hes showed.
Infact we cannot prove a negative, we can only prove positives.

That paper is mess, he makes some very weird assumptions sometimes :normalizing the uv output against a scale which seems to simply be the actionspectrum for suntan saying that its "scientific consensus" among others; Also he was using uvb tubes all day long: uv both stimulates the production thc and cannabinoids as well as breaking it down. Its like a sunscreen for the plant. Tests done by @Prawn Connery showed similar results: uvb flourecents produced less thc than adding some near uv (405nm).
The way the paper is written also makes me suspicious; the way it comes off is straight "no effect from uv" while the results are more nuanced. It makes me wonder if Bugbee has a vested interest somewhere: he sells light measuring equipment that dont register uv. And word has it that wayback, when his meters also wouldnt register far red he supposedly also discounted any effect from far red. But then when his new model was able to measure far red his experiments actually did show an amazing effect of far red. Im not sure, ive not looked fully into it but its enough for me to not see his uv paper as some kinda end all arguments, especially since he actually states that he found an effect of 15% increase in cannabinoids, only he was not able to attribute it to uv due to noise in his numbers.

 

[kro-magnon]

Its not as much trying to convince someone as meeting arguments and making sure that whoever reads this years from now actually get a clear picture. Some people see one person going against the grain and their contrarian nature makes them believe whatever opposite everybody is arguing, that that one guy going up against everyone is the one with the truth.
Its also trying to set a standard of how we discuss things and not being lazy in research or arguments.
HPS is not completely without merit, smoked some great and slightly different smelling gear grown by hps. The problem is when we go led vrs hps instead of trying to figure out what part of hps lighting actually made it to the favorite growlight of litterally everybody before, and how to implement this in a led fixture. I have seen myself how adding light outside of those standard 450/660 led peaks changed the way our bud smelled and smoked and i was very happy with it.
@Crooked8 id wager anything that you could still squeeze out better smelling bud and better high with a more optimized spectrum. Not doubting your grow though, just think that your obvious great results are more down to you and your growgame, along with genetics and a very good setup in general. The agro bar have a reduced green content which i really like but nor reds nor blue/violets/uv is optimized for higher terps and quality.

I agree on the idea giving the best information possible to potential readers, that's why I tried to answer to the posts of this guy but I'm a grower not a scientist so I don't have all the information from this point of view only from my gardener perspective. I lack knowledge to master some of the things discussed here sometimes and being in a foreign language doesn't help either.
I have used HPS for a long time and was happy with the result I had but since I switched to LED my buds are better that's a fact every person who smoke them can agree on. In winter I mix both LED/HPS to have better temperatures and this combo works great as well. I would like to try to add UV and IR to my LEDC bars but it's a bit expensive for my actual budget, I'll wait for the price to drop in 1 or 2 years unless I find a good deal like I had for my Lumatek bars.

 

[Rider420]

Reality check: the sun is far more powerful then any HID or LED light yet indoor weed is better.

 

[zachrockbadenof]

Reality check: the sun is far more powerful then any HID or LED light yet indoor weed is better.

not true... u can grow kickass weed outdoors... if u have the rite conditions... and growing outdoors adds something to weed that indoors can't touch...

 

[kro-magnon]

not true... u can grow kickass weed outdoors... if u have the rite conditions... and growing outdoors adds something to weed that indoors can't touch...

The problem is not many people have the right conditions to grow good weed outdoor, there is more indoor good buds available than good outdoor buds. I have already done a few great plants outdoor the good years but I also had to harvest too early on many plants, this is the main problem who will downgrade the quality of the buds.

 

[Rocket Soul]

not true... u can grow kickass weed outdoors... if u have the rite conditions... and growing outdoors adds something to weed that indoors can't touch...

I agree as far as smells and stone - my top two smokes ever for that were both grown outside and at about 800m elevation. Blue haze had a wonderful smell and the most lovely stone ever, completely relaxed and like i uad the warmth of the sun in my chest. Buddies kept jonesing for more. The smell kept for long time even if i didnt have it kept well.
And for stoney it was Glue trap outdoors, flowered thru the spring (oddly enough but due to a misstake of my buddy): complete face melt of a group of 7 after one joint. Few hours of speechless stoners just zoning out; all more than experienced smokers.

The only thing inhave against outdoor is the tissue texture; hard and fibery, butnin general id reach for outdoors over indoors any day, as long as its properly sunkissed and not some greenhouse weed: glass and plastic reduce the uv and all the magic.

 

[zachrockbadenof]

ahhhh yes conditions... very true its much easier to tune an indoor grow... outdoors u either have the conditions or u don't - i tried for years to grow outside and the plants grew like weeds (ohhh yeah it is a weed), until around sept 20th when the sun doesn't come out as early, and the humidity rises- i'd be out there every day pruning out the rot, and by early oct there is nothing left... the only plant that didn't get rot was a sam the skunk seed, but it never had enough time to get anywhere nearto being finished...

so yeah unless u live on a mountain in maui... or columbia, gotta be indoors...

 

[Ca++]

That's the study. I can't see a gain of statistical significance either. There are blips, but the overall trends are not one's I would want to gamble on.

 

[Crooked8]

View attachment 19043339

That's the study. I can't see a gain of statistical significance either. There are blips, but the overall trends are not one's I would want to gamble on.

This is what i saw, and why i wont race to grab fixtures with UV, yet.

 

[Rocket Soul]

View attachment 19043339

That's the study. I can't see a gain of statistical significance either. There are blips, but the overall trends are not one's I would want to gamble on.

Ca, this is a bit silly, youre kinda showing off that you dont know how to read or understand one of these studies. This is not a graph indicating significance, its indicating measured effect. Significance is not pictured its calculated, its that little P value. And nowhere are they measuring how much buds was grown. You got it wrong, g/m goes with the graph on the right side and refers to canabinoids /m, the left measures concentration in %.
What graph does show is an increase in cannabinoidconcentration of 15% while applying the lowest UV dose, and then the concentration goes down as you apply more.

As expected, uv both stimulates and break down cannabinoids. Especially if you target uvb while giving no UVA.
What does bugbee do then? Try to make a linear correlation out of it when the data indicates that its actually a curve rather than a line.

I know that "looks like blips" is a very handy tool but you really need to read this study in order to understand what a clusterfuck it is. You need to do a bit better. And why do you see this ONE study as the end all one when there are plenty of studies showing both effect and statistics? You cant chose to only see the science of guys that are in youtube, being on youtube is not a preconditions of being right.
Ive gone so many rounds on uv with you that soon ill end up sending you my spare uv diodes so that you try it yourself and believe your own lying eyes. I dont know how much it will push thc in your grow but i can say categorically it will change up smell and taste for the better.

 

[Crooked8]

Ca, this is a bit silly, youre kinda showing off that you dont know how to read or understand one of these studies. This is not a graph indicating significance, its indicating measured effect. Significance is not pictured its calculated, its that little P value. And nowhere are they measuring how much buds was grown. You got it wrong, g/m goes with the graph on the right side and refers to canabinoids /m, the left measures concentration in %.
What graph does show is an increase in cannabinoidconcentration of 15% while applying the lowest UV dose, and then the concentration goes down as you apply more.

As expected, uv both stimulates and break down cannabinoids. Especially if you target uvb while giving no UVA.
What does bugbee do then? Try to make a linear correlation out of it when the data indicates that its actually a curve rather than a line.

I know that "looks like blips" is a very handy tool but you really need to read this study in order to understand what a clusterfuck it is. You need to do a bit better. And why do you see this ONE study as the end all one when there are plenty of studies showing both effect and statistics? You cant chose to only see the science of guys that are in youtube, being on youtube is not a preconditions of being right.
Ive gone so many rounds on uv with you that soon ill end up sending you my spare uv diodes so that you try it yourself and believe your own lying eyes. I dont know how much it will push thc in your grow but i can say categorically it will change up smell and taste for the better.

315 cmh have UV, i believe its specifically UV-B, why are the leds always way more terpy and icy in comparison? Its truly night and day, and the boulder lamps they run are old model leds its really just white and red diodes with no blue or UV diodes. Is it because there is no UV-A? Mind linking a source or study that has data to show that this is beneficial? Im not doubting the possibility at all. I just ran HIDs forever and never got quality like with LED.

 

[kro-magnon]

I would like to improve the stretch of my clones grown under my LED, since I've switched I've noticed the plants don't grow as much as they did during the stretch period with HPS. As I have a very small veg space I was using this explosive growth under HPS to my advantage to get big enough plants, with my LED the clones who are less vigorous than seedlings don't grow as much as I'd like in the first weeks of flowering.Do you think they would grow more vigorously if I was setting the timer on 13/11 for the first 3 weeks then giving 12/12 ?

 

[Prs2xs]

315 cmh have UV, i believe its specifically UV-B, why are the leds always way more terpy and icy in comparison? Its truly night and day, and the boulder lamps they run are old model leds its really just white and red diodes with no blue or UV diodes. Is it because there is no UV-A? Mind linking a source or study that has data to show that this is beneficial? Im not doubting the possibility at all. I just ran HIDs forever and never got quality like with LED.

CMH does NOT have any uv- I have measured it with my solar meter, and it registers 0, right close to the bulb. Philips 4200k bulb, 315w.

 

[Rocket Soul]

315 cmh have UV, i believe its specifically UV-B, why are the leds always way more terpy and icy in comparison? Its truly night and day, and the boulder lamps they run are old model leds its really just white and red diodes with no blue or UV diodes. Is it because there is no UV-A? Mind linking a source or study that has data to show that this is beneficial? Im not doubting the possibility at all. I just ran HIDs forever and never got quality like with LED.

Im with you on CMH, we ran it for a few years and had good results but things got better once we dialed in leds and got some <400nm light in there.

Heres a the spectrum of a Dimlux cmh, uv is the part <400. Not a lot of punch really and looks like it barely covers the UVA region
Also have a look at the right side, loads of infra red. My working hypothesis is that infra red will cook of cannabinoids and terps: it aligns with tentative results from @Prawn Connery who got higher thc from near uv supplementation by leds (405nm) than what they got from using uvb flourecents (who also have a bit of infrared).
And if you think about it, it also lines up with bugbee; he added UVB/infra red and a very small proportion of uva thru fluorescents and only found effect in the lower uv doses. Apart from that: the people ive seen who used uvb flourecents successfully (my buddy Randomblame at RIU, hope surfaces again sometime) indicated that its not to be used for the full day and that uva should be about 3-4x more than uvb.
Bugbee added uvb for full day, the way he measured it was muddled by normalizing it to some kinda of actionspectrum that aligns more to skin eritrema (suntan) and couldnt get his results to statistic significance. But the point is that even though his uv supplement approach was messy and non optimal; he still found effect on low doses, 15% increase. If you find that a little does something, and understand that in normal conditions under sun uv is not constant during the day, that should be enough for a serious scientist to retry the experiment with adjusted conditions.
For uva papers, please ask @Prawn Connery he has a bunch and theyve been posted before in this thread. Im a bit of a mess with keeping all the links to studies but i know how to read and evaluate one once i got it in my hand. Basicly what im saying is that bugbees methodology is a very blunt tool. If you subscribe to the idea of a bad-faith Bugbee this study gives you plenty of arguments for him fudging this study. to take away "uv no effects" from this is absurd, the way he presents his findings look tailored for getting a layman to think it does nothing. All he proves is that his uv approach didnt work consistently enough for him to be able to get the numbers in line to get to statistic significance.

Lets put it like this: say you get some new nutes to try out. You do a side by side with your current nutes. You find that your new nutes produced 15% more bud and after running some statistical tests you find that theres a 50/50 chance that the increase was actually down to the new nutes.
What would be a logical and rational reaction in your opinion?
- Abandon the new nutes and declare to the world that nothing happened, nothing to see here. And then make some youtube videos to promote this even further.
- decide good enough for me changing nute supplier
- think critical about your results, try to analyze the cost/benefit, and run the side by side again?

Bugbee is firmly in option 1.
Personally im in option 3.
Cost/benefit: we kitted out a 2m2 section with 50$ worth of uv diodes (24x 400nm and 12x 365, using generic china/alibaba). Solder iron, wiring and tinn: no more than 30$. 40$ per meter.
Our results was an unmistakable change in terps and smells just being louder, and more defined. I cant say about the stone and thc concentration, dont have measuring equipment for that yet. Its hard to smoke and say what is 20% and what is 23%.

Benefits:
1: well, first of all i learned how to solder led stars, something i was dreading for a long time. This means i can now do my own research and do custom uv spectrums, im no longer bound to the uv strips on offer by the market. They tend to only cover one specific nm, and in my reasoning you should try to have a more continuous coverage of the whole uv spectrum, with a downward slope just like in nature. Btw, anyone afraid of soldering; its much easier than one would think. Buy 10 aliexpress diodes and a soldering iron to train on and you will be good to go. For me personally, together with the information about what uv does in practice is already worth it to me. Hell, id pay for a m2 of uv leds just to get Ca++ to try out and get off my case and eat his hat, lol

2: Was it worth it in quantifiabled measures, ROI etc. this is much more tricky to gauge and depends very much on why and how you grow and market situation. If you grow for yourself: yes, without a doubt. A typical personal stash grower with a 1m2 tent would spend about 0.5kwh per day (thats between 5-10ct around here) of flower and get much better tasting weed with healthier flower growth. Stronger smoke? Not sure if placebo or not but it seems to me. With an initial investment of about 40-50$. Further more, if youre a hobby breeder it makes even more sense; if youre breeding without uv then you will never get a plant that develops to its full potential.


If you grow for comercial: this depends on your market situation but there seems to be a pattern to every place that become a grow mecca: huge influx of players/growers, flooded market with somewhat middy bud and hugely dropping prices. It happened in Oregon, here in barcelona and a few other places, in many cases there are growers that cant even sell their bud. If your able to produce better quality weed than the rest youll have an easier time with competition. But this also means youll have to be able to move a bit yourself as a grower; if its a buyers market and you can only use one place to offliad your product it may be better to just go for quantity over quality.
The best scenario for uv use imo opinion is when your in a market full of average bud, when your limited by space rather than amps, and when you can shop around a bit to off load your goods. This is the situation we grow in so it makes sense to us, even if we are slightly amp limited. We need to make every tray produce as much as possible and it needs to be in superior quality. If not we get buyers that lowball us and prices drop about 10% and we have problems moving it. If your in a similar situation, cant expand to more trays, and youre already at the top of your yield game then how else are you going to improve profitability other than raise your quality? You simply show your regular bud to your distributor and your uv bud, and ask how much more theyll pay you for better quality. If they say 0 then shop around. If you can move up 10-20ct per gram youve not only made profits youve also improved your market situation; if the market goes to shit youre the least likely to be affected.

Wow, this is getting into tldr so ill just make a final point and its about personal and growers pride: if youre doing something you should always try to do it well, to be at the top of your game. For someone who is obviously a great grower like you, it seems like a minimal investment in order to get a new level to your growgame, even if its just a educated guess or chancing. As a good grower (im not, i do the technical side of things at ours and im away from the day to day) its very easy to get caught up in the "Great grower fallacy": "ive done this for many years and honed my skills, why should i take on the advice and spend a bunch of cash based on the advice of someone whos not seen all that ive seen and when im already getting great results?" Well, being good doesnt mean you cant get better. I do understand the hesitation, both to get a bunch of expensive equipment and the daunting nature of DIY. But there is every reason to try it out, albeit in a carefull and balanced approach, even if its just to grow even more like a boss.
Ive been making lights for this grow since 2018 and tried most things, some fads and some things really worked out. Im beyond convinced that there are still gains to be had by tweaking things for those last few points. By now im almost ready to bring some gear to the market the market but im working with a limited cashflow. If youre not convinced yet then lets get back to this when i get something that can give you undebatable results without any diy fuzz
Also, dont get too caught up in efficiency, its a trap: all efficiency does is regulate how much power you need to get to your target light levels. You can achieve the same light levels by just upping your watts by a few %. I posted a paper a bit back on red supplement which makes me believe that the next step in growlights is not efficiency its light utilization value: how much more bud you can get by tweaking your spectrum. There seems to be about 15% of gains to be had by just optimizing your spectrum. To put it into context; a 2.6 ppf/w light but with tweaked spectrum should grow similarly to a 3.0 standard HE light, with the added benefit of higher quality bud.

Sorry for being long winded

 

[Rocket Soul]

I would like to improve the stretch of my clones grown under my LED, since I've switched I've noticed the plants don't grow as much as they did during the stretch period with HPS. As I have a very small veg space I was using this explosive growth under HPS to my advantage to get big enough plants, with my LED the clones who are less vigorous than seedlings don't grow as much as I'd like in the first weeks of flowering.Do you think they would grow more vigorously if I was setting the timer on 13/11 for the first 3 weeks then giving 12/12 ?

For more stretch, Far red on a separate channel.

 

[Orange's Greenhouse]

"Cannabinoid concentration in the lowest UV treatment was about 15% higher than the control in rep one and 10% higher in rep two, but the effect was not statistically significant."

What does this mean?

The key term here is statistically significant. There are two ways to explain it:

The worst plant in their treatment group had lower cannabinoid concentration than the highest control plant.

If they threw all buds in a bucket and then tried to sort them back into "treatment" or "control" buckets they had some leftover where the result is ambiguous. It could be either group because there is no difference.


Tbh this paper is not really relevant to our hobby. He's growing CBD weed and from there makes assumptions about THC rich weed (implicitly). I would like to see it replicated with relevant genetics and then it is worth to dissect their statistic and methods.

 

[Orange's Greenhouse]

significance is not pictured its calculated, its that little P value.

You can read significance in that graph. The standard error is at 95 % confidence interval. If it overlaps there is no statistically significant difference (at 95 % CI).