Should I add UVB Light?

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Moe.Red

Moe.Red

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Nothing to report today - no UV - except that my PH took a dive on me to 4.2 I don't know why.

Yesterday I did a 30 gal water change bringing PPM to 140. I added back in 1:2:3 GH trio to 280. That's a solid range for me.

I also added in some biologics - normal shit. Done this kinda thing 1000 times.

Plants look unchanged from yesterday. I'll watch this closely tonight. If it happens again I'll look at roots. Just a PITA with the scrog nets in the way and a friggin tree of buds to be careful of.

I'm off tomorrow so I'll make a decision about UV timing when the plants wake up tomorrow and I can get a look at them.
 
Milson

Milson

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Nothing to report today - no UV - except that my PH took a dive on me to 4.2 I don't know why.

Yesterday I did a 30 gal water change bringing PPM to 140. I added back in 1:2:3 GH trio to 280. That's a solid range for me.

I also added in some biologics - normal shit. Done this kinda thing 1000 times.

Plants look unchanged from yesterday. I'll watch this closely tonight. If it happens again I'll look at roots. Just a PITA with the scrog nets in the way and a friggin tree of buds to be careful of.

I'm off tomorrow so I'll make a decision about UV timing when the plants wake up tomorrow and I can get a look at them.
Will you be showing pics etc tonight anyway?

Also....are you sure the pH instrument is correct?
 
Moe.Red

Moe.Red

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Will you be showing pics etc tonight anyway?

Also....are you sure the pH instrument is correct?
Wasn't gonna, but for you, mmmmmmok.

PH probe was calibrated at the beginning of this run. I verified it with a pen and they were close. The probe on the wall is more accurate.


Daay 4 UV


Day 4 Control



Do you see more trichomes?
 
Milson

Milson

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So i am expecting more sessile trichomes as the most visible first sign here.

Day 1 UV2


Day 1
Screenshot 20210401 181900


Day 3
Screenshot 20210401 181841


I am watching that area because i think i might see an increase there.

Upon similar zooming in the control i wasn't seeing as much of interest.

Very early days yet of course.
 
Moe.Red

Moe.Red

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I will work on clearing up and zooming in on that area. Got one picked out on the control?

wait I probably already have pics focused on that area. I’m free handing this over my shoulder height with my arms extended so I’m taking like 20 pics at a time and praying lol. I really need to buckle down on my photography skills if I’m gonna keep this up.
 
Milson

Milson

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I will work on clearing up and zooming in on that area. Got one picked out on the control?
Not really. I looked around and nothing quite jumped out. I'd love to hear others' takes upon zooming in on pics though....i think those from today and tomorrow are enough time to see the first signs of results. (The sessile trichs are the ones that look like balls instead of the stalked ones with a head, for those unaware).
 
Moe.Red

Moe.Red

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I’ll figure out how to just dump all the pics somewhere people can download from and see all the areas at several focal planes. I’ll bet somebody good with photoshop could somehow blend them. Not me tho I know my limits
 
DennisBrown

DennisBrown

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I assume Dennis is at solacure? If so and you are in contact with him mention we are publicly testing his bulbs on this thread and see if he wants to participate. He very well may be the guy that can give us the data we are missing. It'd be cool to talk to the manufacturer, sorta like a Reddit AMA

Finally got here. Been a heck of a week. I want to be careful to not upset any mods, but I'm happy to answer any questions. For those that don't know, I've worked with nothing but UV for 30 years, and with cannabis growers for 20 years, and we invented the dedicated UVB bulb for cannabis a long time ago, so I'm fairly up on what's real and what's rumor.
 
Moe.Red

Moe.Red

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Finally got here. Been a heck of a week. I want to be careful to not upset any mods, but I'm happy to answer any questions. For those that don't know, I've worked with nothing but UV for 30 years, and with cannabis growers for 20 years, and we invented the dedicated UVB bulb for cannabis a long time ago, so I'm fairly up on what's real and what's rumor.
Welcome aboard.

Have you had a chance to see the finding so far? I would love your thoughts on our testing method and parameters and any suggestions you might have.

We are working on confirming predictions of higher THC, more trichomes, and potentially lower minor cannabinoids.

I have run these bulbs before and fried plants using the instructions sent with the bulbs. This is an attempt to find the correct protocol for success with UV
 
Jp OGfarmer

Jp OGfarmer

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Iv lights should only be used in the last several weeks. The iv attacks the plants health and the autoimmune response is more oils. But you can’t look and see trichone increase without a side by side. Really you can only tell is with side by side, then test the levels. But if you use it the entire time the attack will lower your plants vigor, not improve it.

I don’t use cyco , but it is probably one of the best lines for single manufacturer use. Follow their recipe. Moab looks surprisingly a lot like miracle grow and has nothing in my experience to even come close to helping the Cyco line of chelated nutrients. Again great product for quality, maybe not production
 
DennisBrown

DennisBrown

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Welcome aboard.

Have you had a chance to see the finding so far? I would love your thoughts on our testing method and parameters and any suggestions you might have.

We are working on confirming predictions of higher THC, more trichomes, and potentially lower minor cannabinoids.

I have run these bulbs before and fried plants using the instructions sent with the bulbs. This is an attempt to find the correct protocol for success with UV

We've done a couple hundred tests, and one of the reason I came to dispel some myths, like I've seen here and everywhere. For starters, it is not true that you should only use UVB in the last couple of weeks. You CAN do it that way, and get a nice bump in trichomes, but you have to dig a little deeper and understand more about why we are using UVB to begin with: UVR8.

I recommend starting UVB in the 280-290nm region as soon as you flip. Don't wait. The reason is that we are trying to trigger the UVR8 protein from day one of flower. UVR8 is a photosensor, but it doesn't measure day/night length, it measures UVB, and is most sensitive from 280-290nm. This is why tanning bulbs and reptile lights aren't very effective, they stay above 300nm. Btw, all plants have the UVR8 protein, not just cannabis. They all react differently to the chemical signals that the protein sends to the plant. Tomatoes develop thicker flesh and more flavonoids. Sorghum matures faster, so you can get 4 cuttings a year instead of 3. Cannabis creates more trichomes/THC, but ONLY because THCa has a super high absorption index for UV. Basically, UVR8 says "Hey, we are getting pounded by UV" and the mother plant reacts by coating the buds because she thinks she's going to have seeds in there, and exposing seeds to UV will cause DNA damage and reduce how many are viable. This is why breeders should NOT use UVB, but everyone else should.

So you start from day one of flower to keep the plant in defense mode during the entire flowering season. The other reasons you do this are to kill PM before it starts, when it is still a spore, and reduce stretch, reducing internodal distances on the plant. On average, a plant that is hammered with our Flower Power UVB lamps for 2-3 hours a day will be around 6" shorter than ones that weren't, based on testing with clones. This varies by strain, but regardless, it is noticeable. This is because the plant is in "defense" mode, and is reallocating resources from growing stems, to growing trichomes. There is no difference in yield, up or down, it's just higher in THC. Going from 18 to 26%, 22 to 29% and 26 to 34% is certainly doable and is being done by experienced growers with a little experience with the bulbs, pushing the times up a bit. You don't get that by only using UVB in the last two weeks. How you do that, I will leave for another post, this one is long enough as it is ;)
 
Milson

Milson

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First off, welcome @DennisBrown ! I really enjoyed your interview w uk hydro mag. How i started investigating uvr8.

Just off the cuff, the claim that there is no difference in yield seems to be one that merits further investigation. It surprises me that the plant would only spend resources it would not have put into more bud weight in its attempts to protect itself from UV.

Definitely something we can test further here though!
 
DennisBrown

DennisBrown

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First off, welcome @DennisBrown ! I really enjoyed your interview w uk hydro mag. How i started investigating uvr8.

Just off the cuff, the claim that there is no difference in yield seems to be one that merits further investigation. It surprises me that the plant would only spend resources it would not have put into more bud weight in its attempts to protect itself from UV.

Definitely something we can test further here though!

That was our fear many years ago, but even Rosenthal will tell you it doesn't affect yield. The plant reduces what it doesn't need, more stem, but if anything, you would think she wants to make MORE seeds to deal with the potential loss of viability, thus bigger buds. But it just didn't pan out that way. We haven't tested in a while specifically for that because we were sufficiently convinced, but average yields always came in within 3%, sometimes higher, sometimes lower, but always around 3% or less. To me, that is well within the statistical margin of error, thus we feel confident saying that there is no change in yield. Again, we were expecting a change in yield when we tested; maybe up but probably down, so we were surprised when it basically did nothing to yield in the tests.

Same for bud density. I've had some claim that they make it more dense, but most say it didn't make a difference one way or another (this is from feedback from many growers, not a test), so I would conclude UVB probably doesn't affect bud density, and it was something else they were doing that made the buds more dense. We can't test for everything, but working with growers 20 years has helped to amass a lot of feedback, and there are some convincing patterns.

We have limited testing on the other cannabinoids, which appear unaffected by UVB. There are some tricks you can do with UVB to bump CBD by .5 to 1% total, but really not worth the effort and it isn't completely proven.
 
DennisBrown

DennisBrown

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Is this add on light for the Gavita 1700 what you guys are talking about?


Probably worth mentioning that NO UVB LEDs exist that work. UVA, sure, and UVA is great for photosynthesis, but UVB LEDs in any spectrum that is worthwhile, do not exist. Every week I'm talking to makers, but UVB is a special pocket of frequencies that tends to burn out or destroy the packaging. Any LED that says "UV" is really talking about UVA only. Until they get UVB below 300nm that won't burn out after 100 hours, fluorescent is the only game in town for UVB. MH, CMH, etc, all have a tiny amount of UVA, no UVB.
 
Milson

Milson

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That was our fear many years ago, but even Rosenthal will tell you it doesn't affect yield. The plant reduces what it doesn't need, more stem, but if anything, you would think she wants to make MORE seeds to deal with the potential loss of viability, thus bigger buds. But it just didn't pan out that way. We haven't tested in a while specifically for that because we were sufficiently convinced, but average yields always came in within 3%, sometimes higher, sometimes lower, but always around 3% or less. To me, that is well within the statistical margin of error, thus we feel confident saying that there is no change in yield. Again, we were expecting a change in yield when we tested; maybe up but probably down, so we were surprised when it basically did nothing to yield in the tests.

Same for bud density. I've had some claim that they make it more dense, but most say it didn't make a difference one way or another (this is from feedback from many growers, not a test), so I would conclude UVB probably doesn't affect bud density, and it was something else they were doing that made the buds more dense. We can't test for everything, but working with growers 20 years has helped to amass a lot of feedback, and there are some convincing patterns.

We have limited testing on the other cannabinoids, which appear unaffected by UVB. There are some tricks you can do with UVB to bump CBD by .5 to 1% total, but really not worth the effort and it isn't completely proven.
Have you noticed a difference in response or tolerance from cannabis from different regions? Certainly different parts of the globe have different uv regimens....
 
shaganja

shaganja

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We've done a couple hundred tests, and one of the reason I came to dispel some myths, like I've seen here and everywhere. For starters, it is not true that you should only use UVB in the last couple of weeks. You CAN do it that way, and get a nice bump in trichomes, but you have to dig a little deeper and understand more about why we are using UVB to begin with: UVR8.

I recommend starting UVB in the 280-290nm region as soon as you flip. Don't wait. The reason is that we are trying to trigger the UVR8 protein from day one of flower. UVR8 is a photosensor, but it doesn't measure day/night length, it measures UVB, and is most sensitive from 280-290nm. This is why tanning bulbs and reptile lights aren't very effective, they stay above 300nm. Btw, all plants have the UVR8 protein, not just cannabis. They all react differently to the chemical signals that the protein sends to the plant. Tomatoes develop thicker flesh and more flavonoids. Sorghum matures faster, so you can get 4 cuttings a year instead of 3. Cannabis creates more trichomes/THC, but ONLY because THCa has a super high absorption index for UV. Basically, UVR8 says "Hey, we are getting pounded by UV" and the mother plant reacts by coating the buds because she thinks she's going to have seeds in there, and exposing seeds to UV will cause DNA damage and reduce how many are viable. This is why breeders should NOT use UVB, but everyone else should.

So you start from day one of flower to keep the plant in defense mode during the entire flowering season. The other reasons you do this are to kill PM before it starts, when it is still a spore, and reduce stretch, reducing internodal distances on the plant. On average, a plant that is hammered with our Flower Power UVB lamps for 2-3 hours a day will be around 6" shorter than ones that weren't, based on testing with clones. This varies by strain, but regardless, it is noticeable. This is because the plant is in "defense" mode, and is reallocating resources from growing stems, to growing trichomes. There is no difference in yield, up or down, it's just higher in THC. Going from 18 to 26%, 22 to 29% and 26 to 34% is certainly doable and is being done by experienced growers with a little experience with the bulbs, pushing the times up a bit. You don't get that by only using UVB in the last two weeks. How you do that, I will leave for another post, this one is long enough as it is ;)
Wow! Thanks for this needed Info! So awesome! My last grow had them on the whole time, In A greenhouse. For sure, much more sand in the bags. Smoke was more potent than previous. And also have a more ceilingless high. did three hours middle of day. I did however, have a complete change of expression from a cbd plant. I expected a typical cbd warm shower type buzz from Harley m.d. but the buzz from this pheno is not relaxing at all. Have you found any evidence of uvb changing cannabinoid expression? Maybe its just an outlier. Thnx
 
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