Should I add UVB Light?

[Moe.Red]

Yeah I would be curious to confirm if that's the case... only the last 2 weeks.

Here is the testing setup:

And here are the bulbs:

All that's left is to figure out when the last 2 weeks are in this tent, and when and for how long to run them.

 

[Aqua Man]

Here is the testing setup:

And here are the bulbs:


View attachment 1094503

View attachment 1094505


All that's left is to figure out when the last 2 weeks are in this tent, and when and for how long to run them.

Looks good and sounds like a good timeline. Have you figured out duration? I'm really busy until turesday but if ya need some help for that I'm more than willing to look into it.

 

[Aqua Man]

Happen to know how many micro watts those put out of UVA and UVB at that distance from the plants? Would come in handy for figuring it out.

 

[Moe.Red]

Happen to know how many micro watts those put out of UVA and UVB at that distance from the plants? Would come in handy for figuring it out.

no, I need a proper UV sensor. I’m looking right now.

ok I just bought sensors arriving on the 26th. We will get this mapped out before we need to turn them on.

 

[LaVirtue]

Here is the testing setup:

And here are the bulbs:


View attachment 1094503

View attachment 1094505


All that's left is to figure out when the last 2 weeks are in this tent, and when and for how long to run them.

omg this is really cool!

 

[Moe.Red]

So the next step is to figure out when to turn on the UVB. I have meters now for UVA + UVB and UVB Only, so I'll do some testing and see what the output is at what distance. But I also need to guess what is the last 2 weeks here. This is an outer leaf on a lower bud of the White Widow that will set the harvest time.

Anybody wanna guess how much longer?

 

[MIMedGrower]

@Moe.Red you cant properly determine harvest time from a leaf. You have to average the calyx trichomes over the whole plant to determine its truly finished. And not until its actually finished growing if you want any good potential out of it.

just a tip. Leaf trichomes turn early many times and are a poor indicator of overall ripeness.

I would wait til the buds are fully expanded and most pistils have turned dark and mostly died back and the bud trichomes are 50% cloudy to determine 2 more weeks.

this is likely 2 weeks past most growers patience. And why most weed doesnt really get a high tolerance user high.

And i know this isnt your plan and you invested but i think adding uv at this point may raise thc numbers but at the cost of what while stressing the plant at its weakest point?

just a thought. And you have no baseline without the same cuts in a non uv tent under the same exact conditions anyway.

Its not like there is a fixed amount of ripening trichomes. They keep producing more and more if not yellowed and killed off early by too much pk or an impatient grower. I like to look into the bud with a scope and see layers and layers deep into the flower.

 

[LaVirtue]

@Moe.Red you cant properly determine harvest time

just a tip. Leaf trichomes turn early many times and are a poor indicator died back and the bud trichomes are 50% cloudy to determine 2 more weeks.

this is just a thought. And you have no baseline without the same cuts in a non uv tent more and more if not yellowed and killed off early by too much bud with

@Moe.Red you cant properly determine harvest time from a leaf. You have to average the calyx trichomes over the whole plant to determine its truly finished. And not until its actually finished growing if you want any good potential out of it.

just a tip. Leaf trichomes turn early many times and are a poor indicator of overall ripeness.

I would wait til the buds are fully expanded and most pistils have turned dark and mostly died back and the bud trichomes are 50% cloudy to determine 2 more weeks.

this is likely 2 weeks past most growers patience. And why most weed doesnt really get a high tolerance user high.

And i know this isnt your plan and you invested but i think adding uv at this point may raise thc numbers but at the cost of what while stressing the plant at its weakest point?

just a thought. And you have no baseline without the same cuts in a non uv tent under the same exact conditions anyway.

Its not like there is a fixed amount of ripening trichomes. They keep producing more and more if not yellowed and killed off early by too much pk or an impatient grower. I like to look into the bud with a scope and see layers and layers deep into the flower.

@Moe.Red you cant properly determine harvest time from a leaf. You have to average the calyx trichomes over the whole plant to determine its truly finished. And not until its actually finished growing if you want any good potential out of it.

just a tip. Leaf trichomes turn early many times and are a poor indicator of overall ripeness.

I would wait til the buds are fully expanded and most pistils have turned dark and mostly died back and the bud trichomes are 50% cloudy to determine 2 more weeks.

this is likely 2 weeks past most growers patience. And why most weed doesnt really get a high tolerance user high.

And i know this isnt your plan and you invested but i think adding uv at this point may raise thc numbers but at the cost of what while stressing the plant at its weakest point?

just a thought. And you have no baseline without the same cuts in a non uv tent under the same exact conditions anyway.

Its not like there is a fixed amount of ripening trichomes. They keep producing more and more if not yellowed and killed off early by too much pk or an impatient grower. I like to look into the bud with a scope and see layers and layers deep into the flower.

Does PK turn trichomes yellow prematurely?

 

[MIMedGrower]

Does PK turn trichomes yellow prematurely?

no without balanced nitrogen the plants yellow sooner.

 

[Moe.Red]

We are coming up on the 2 week timeframe, time to finalize this test.

My only concern is the amount of UVB and for how long. Does anyone have a link to a relevant study handy? I've been looking thru my history and I cannot find that study that resulted in THC boost so I can replicate the test. Hopefully @Aqua Man has it at his fingertips.

Just bought a second GoPro and setting that up to get better footage.

It's popcorn time buddies!

 

[Milson]

We are coming up on the 2 week timeframe, time to finalize this test.

My only concern is the amount of UVB and for how long. Does anyone have a link to a relevant study handy? I've been looking thru my history and I cannot find that study that resulted in THC boost so I can replicate the test. Hopefully @Aqua Man has it at his fingertips.

Just bought a second GoPro and setting that up to get better footage.

It's popcorn time buddies!

Lying to UV – milson's place

 

[Moe.Red]

Thanks @Milson you are Johnny on the spot with the studies. I love the library you are building on your blog.

Here is a video that describes the test. Next thing to do is to apply Milson's paper to my grow setup.


Setup for UVB effects on cannabinoid testing
First in a series working to determine if application of UVB during the last 2 weeks of flower on cannabis sativa increase cannabinoid levels in the plant as has been previously stated.

 

[Domon8n30]

UV light definitely increases trichome production that's a fact...

 

[Milson]

UV light definitely increases trichome production that's a fact...

@Moe.Red is in the process of independently verifying said fact, which will be very interesting no matter his result so long as everything is documented with his usual detail.

 

[LaVirtue]

This is very cooI & I’m psyched to see what happens.

I can’t believe the article too. Crazy that they studied it.

 

[Pondracer]

My interest in it was more pest and mold control. For those purposes I do like mine.

 

[Moe.Red]

My interest in it was more pest and mold control. For those purposes I do like mine.

For me it would not be effective except across the top of the canopy. Too many plant parts to get in the way to allow penetration.

I'll bet short blasts of UVC would be better for that purpose. But that is a whole different can of worms.

And then there is this, my friend @Snaggleroots sent me, perhaps meaning that those "pests" might also be a benefit to a certain point where the plant initiates protection mode and plant physiology changes due to the input:

https://www.researchgate.net/public...r_Nutrient_Extraction_from_Symbiotic_Microbes

 

[Moe.Red]

UV light definitely increases trichome production that's a fact...

Not being a prick here, but your statement is not specific enough. What spectrum? How long per day at what uW/cm2? Does added trichomes (assuming "it" actually does this) result in higher cannabinoids, or perhaps only some, skewing the plant in one direction? How much is too much?

Also, how is your trichome production quantified? Visually?

What if you have a plant that is 2% CBG and the UVB causes that to all get processed into THC, which eliminates the CBG in the resultant plant and starves CBD and others for the base molecule it needs to form? Is that a benefit as many people claim or detriment?

Does UV (AB or C) effect terpenes?

See, I have questions. Proof is in the pudding.

This test will be looking just at the last 2 weeks of flower. UV in its varying spectrums is available to the outdoor plant thru the entire grow in many regions. People say the best weed comes from along the equator, and speculation is the light spectrum. So why just the last 2 weeks?

I just want to figure this stuff out and document. I've done similar testing before, and I do not have it properly documented, so this is the pics or it didn't happen approach.

 

[Moe.Red]

Looks good and sounds like a good timeline. Have you figured out duration? I'm really busy until turesday but if ya need some help for that I'm more than willing to look into it.

Coming down to the wire I'd love to hear your thoughts. We have a perfect opportunity to do a real test here, I don't want to screw this up with bad testing parameters and get no usable results.

 

[Aqua Man]

Coming down to the wire I'd love to hear your thoughts. We have a perfect opportunity to do a real test here, I don't want to screw this up with bad testing parameters and get no usable results.

What's the brand and wattage again?