How much UVB to give.

jimihendrix1

jimihendrix1

Well-Known Member
Leaf Stress is usually the first sign. Second the leaves get fried, and either kill the plant, or severely injure it.. What one is trying to do is push it as far as you can, and not burn the plant.
 
jimihendrix1

jimihendrix1

Well-Known Member
Yes. Start out slow, and work up over a week, or 10 days. Some strains will also have a better response. Plants with origins from near the Equator, and or high altitude will benefit the most.

A mountain in Equador ( 20,000 feet ) had UVA/B as high as what is on Mars.
Ya know the UV index they have on the weather?? Goes from 1-10??? UVA/B in Equador measured a 26, on the 1-10 scale.
 
jimihendrix1

jimihendrix1

Well-Known Member
No Dimmer.

I use them at 24 inches. I run 2 in a 4 x 4 and 1000w HID/Hortilux HPS.
If you have a less powerful light than my 1000w HID, and have to run them closer, then you would need to run the UVA/B less as the closer it is, the more powerful it is.
 
B

Bookush34

Well-Known Member
Thank you for all the reply’s.
I see their is still a large difference between growers as to how much to use.

but I like the idea of slowing working up and watch the plants.
I think I’ll try
0-1-0-0-1-0-0-1-0-0-1-0 for a cycle in 12/12.
Probably start at 30” as that where my hood for my cobs are sitting.
 
Doug Dawson

Doug Dawson

Well-Known Member
jimihendrix1 said:
Im not saying it sir. SCIENCE says the Protein Receptor UVR8, which causes stress to the plant is only activated at 280nm-305nm. Take it for whatever you wish.

Not my opinion. Its plant physiology. Scientific fact.

So yes, to INCREASE THC if the light is not in the 280nm-305 range, its useless. The plant needs all forms of UVA/B as it evolved with it, but the UVR8 Protein is triggered at 280nm-285nm - 305nm. No getting around it.
It also takes special glass to transmit this wavelength.



UV-B resistance 8 (UVR8) also known as ultraviolet-B receptor UVR8 is an UV-B – sensing protein found in plants and possibly other sources.[2] It is responsible for sensing ultraviolet light in the range 280-315 nm and initiating the plant stress response. It is most sensitive at 285nm, near the lower limit of UVB.
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So you use Solacure and on their website it says "We have reason to believe that UVA is also beneficial. While it doesn't stimulate THC production, it penetrates much more deeply than UVB and may stimulated trichome production, which makes THC possible." So what do you feel that means? I don't disagree that hitting the plant with destructive UV in the low UVB band is effective for increasing THC but what do you think increased trichome production will do?
 
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jimihendrix1

jimihendrix1

Well-Known Member
Still the UVR8 Protein is NOT activated unless its 280nm. As I said. UVA is also important, as everything evolved with UVA, and UVB. Obviously you overlooked, dont care about me stating UVA is also important.

Bottom line is UVR8 is NOT activated if not exposed to 280nm/285nm-305nm.
 
Doug Dawson

Doug Dawson

Well-Known Member
jimihendrix1 said:
Still the UVR8 Protein is NOT activated unless its 280nm. As I said. UVA is also important, as everything evolved with UVA, and UVB.

Bottom line is UVR8 is NOT activated if not exposed to 280nm/285nm-305nm.
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I am not disagreeing with that point.
Edit. You are stating a scientific fact about UVR8, I am not trying to debate that with you. Clearly you have done much more research on this and I am more than happy to accept your knowledge about it. I am more curious about what UVA does, why you feel it is important and what effects it has on the plants. Increased trichome production is a good thing.
 
jimihendrix1

jimihendrix1

Well-Known Member
I said UVA is important long ago. Plants, and animals evolved with both. I think Solacure statement speaks for itself. UVA is also important, but to highly stress the plant, one must activate the UVR8 protein.
Seems like they mean UVA could be a Precursor to Trichome production, but it still takes 280nm to produce stress induced damage, forcing the plant to change the chemical profile. Just because one has more trichomes, does not mean they are more psychoactive.
More Trichomes does not mean higher psychoactivity.

The reason I started using UVA/B was to replicate the sun as best as I can.

So for me I ask the question?? Does the SUN emit UVB??? 280nm??? YEP. So for me, if the bulb aint producing 280nm, its not replicating the sun. Bottom line. Anything that has ZERO 280nm light, is useless for my purposes. YMMV. Mine dont.

Ive seen hemp with huge gland production, but no THC
5% of UVB makes it to earth.
 
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Doug Dawson

Doug Dawson

Well-Known Member
jimihendrix1 said:
I said UVA is important long ago. Plants, and animals evolved with both. I think Solacure statement speaks for itself. UVA is also important, but to highly stress the plant, one must activate the UVR8 protein.
Seems like they mean UVA could be a Precursor to Trichome production, but it still takes 280nm to produce stress induced damage, forcing the plant to change the chemical profile. Just because one has more trichomes, does not mean they are more psychoactive.
More Trichomes does not mean higher psychoactivity.

The reason I started using UVA/B was to replicate the sun as best as I can.

So for me I ask the question?? Does the SUN emit UVB??? 280nm??? YEP. So for me, if the bulb aint producing 280nm, its not replicating the sun. Bottom line. Anything that has ZERO 280nm light, is useless for my purposes. YMMV. Mine dont.

Ive seen hemp with huge gland production, but no THC
5% of UVB makes it to earth.
Click to expand...
Thanks for taking the time to respond and share your knowledge. I appreciate it.
 
Doug Dawson

Doug Dawson

Well-Known Member
jimihendrix1 said:
Looks pretty good huh?? 0 THC.

HEMP!!!!



View attachment 4740675
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LOL, yes it does. Now let's say you want to make rosin, it seems like increased trichomes would produce more product? If one added UVA and managed to increase trichome production would that not create more resin? I am not talking about increased potency from UVB damage, I am talking about volume.
 
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