UV LEDs to supplement COBS - Worth it or just chuck reptile bulbs in?

[Huktonponics]

Hello folks. Ive been mulling over the idea of adding some UV leds to my 36 x citizen clu048 3000k & 3500k cobs since i got rid of my cdm gear, and would like to know what you guys think of the following leds.

My area is 2.4 x 1.2m
24 x clu048 1212 3500k
12 x clu048 1212 3000k
12 x epistar 3w far red diodes

Ive found the following UV leds

EPILEDS 10w -Ultra Violet 395nm: Forward Voltage: 10V-12V Forward Current: 700-1050mA Output: 70 lumens visible (mostly UV)

Epistar 5w -UV Ultra Violet 395nm: Forward Voltage: 3.6V-3.8V Maximum Current: 1400mA Output: 80 lumens

Would either of these be any good so that i dont have to mess around with reptile bulbs or those crazy uvb fluros ?

If so how many would be enough to stress them enough to see an increase in resin production ?

I dont find much info regarding UV diodes or LEDS, but some of the more expensive fixtures now have them, so if anyone has any experience or views on them, let me know.

Bless

 

[TurboBucket]

If you're going to do UV don't bother with LED. The spectral output is quite narrow. A tube light will be a much better source. Either reptile bulb or some actual horticulture uv bulbs every fluorescent has a slice of UV.

 

[Orlando Scout]

I agree! I have a nice led set up that has the t5 uvb bulbs attached with its own switch. I love it I can definitely see an increase in resin and trich production. I hope this helps!

 

[PurpleGunRack]

There's a big difference between UV - A, B and C.

The 395nm is mostly if not only UV-A.

If so how many would be enough to stress them enough to see an increase in resin production ?

Nobody knows, it's all based general plant knowldge and on assumptions based on indicas growing at high altitudes, there is zero scientific data supporting the idea that adding UV-B will increase resin production in cannabis.

Check out the UV thread: UV lighting thread

The lamps that have UV, have it as a selling point more than anything else, so they have something special the competition doesn't have.

If I were you I'd get some 660nm in stead of chasing the UV ghost Especially if your COBs are 80 CRI

 

[Orlando Scout]

There is also no scientific data that states uvb doesn't work either. You just have to find out for yourself. In my experience plants I've used uvb on were more potent than identical strains without uvb. But again that's just my experience with it.

 

[PurpleGunRack]

There is also no scientific data that states uvb doesn't work either

That's reversed science, please stick to common scientific practise and supply tangible data to support your theories.

There's also no scientific data that states that sacrificing a virgin at full moon won't increase your yield and potency tenfold.

You just have to find out for yourself.

You *can't* find out for yourself, no grower has the capacity to carry out the extensive tests needed to form a scientific foundation that can give a picture of the increased THC% return achieved by adding UV-B.

In my experience plants I've used uvb on were more potent than identical strains without uvb.

Identical strains? You mean clones, right?

You grew the same clones, at the same time, excactly the same way, with only a UV bulb as the difference and measured the total THC output of the two batches? Or the THC% of the compared buds?

I'm not trying to pick a fight here @CavScout420 just trying to separate the real data from the LED marketing scams that keep bewildering growers every day.
Loose assumptions (lies) about IR, UV and artificial light in general have been repeated so many times, it has become actual science in the back of many people's minds.

 

[Orlando Scout]

So you found scientific data saying that uvb has no benefit to a cannabis plant? All I'm saying is scientific data doesn't prove everything some times you just have to find out what works best for you. Especially on this subject there isn't enough scientific data to prove either of our sides, but instantly my side is wrong because you don't use uvb. Have you ever even tried uvb on a crop?

 

[Orlando Scout]

I'm not trying to argue!! The reason I joined this forum was to stay away from the drama. We all have an opinion ill stick to mine you stick to yours.

 

[Huktonponics]

Im on the fence still about the UV buti figured as my 3500k are 90cri and my 3000k are 80cri and i have some 660nm reds in there already, its either add some UV or some royal blue diodes.

Im just on my way out the door now with the missus as its her birthday, but ill indulge some more later, thanks for popping in guys, appreciated.

Hukt

 

[TurboBucket]

For there being no scientific research on it a Google search certainly yields an awful lot of info.

 

[Orlando Scout]

I found quite a bit on Google aswell most of which said that marijuana do benefit from certain amounts of uvb.I start slow to get them use to it a little. Around 3 weeks before harvest 1hr on in the middle of my 12hr light on cycle. Then slowly move up to 2hrs on in the middle of my 12hr lights on. Then the last 2 weeks before harvest I run them on for 4hrs in the middle of my 12hr light on cycle. For example my lights go on at 7am off at 7pm so I turn my uvb on at 11am then I turn them off at 3pm for the last 2weeks. I've done this with great success!!! Hope it helps!!

 

[PurpleGunRack]

So you found scientific data saying that uvb has no benefit to a cannabis plant? All I'm saying is scientific data doesn't prove everything some times you just have to find out what works best for you. Especially on this subject there isn't enough scientific data to prove either of our sides, but instantly my side is wrong because you don't use uvb. Have you ever even tried uvb on a crop?

You totally misunderstood my post...

I'm not on any side, I don't care if UV increases potency or not, I don't have any stakes in shorting UV lamp producing companies, I just want proof that something works before I spend money on it.

I never said UV doesn't increase potency, at all, where did you read that ???

It doesn't matter what I tried or what I use, my subjective experience isn't worth anything, only proper data from actual tests matters.

For there being no scientific research on it a Google search certainly yields an awful lot of info.

I found quite a bit on Google aswell most of which said that marijuana do benefit from certain amounts of uvb

Google is not a scientific review, it's a search engine, find some useful data, not just loose assumptions, and post a link.


@Huktonponics If you want to add UV-B you need the UV tubes or reptile bulbs, the diodes are mostly UV-A which might have positive effects of its own.

The blues can be used to reduce stretch a little, and is also said to increase potency.

 

[TurboBucket]

https://doi.org/10.1111/j.1751-1097.1987.tb04757.x

UVB UVA Study Test Results Increases Medical Marijuana Potency 3-5%: UVB UVA Lighting Study Results Increases Medical Marijuana Potency 3-5%

Not much, couple of quick results from my search engine.

Removing UV-A and UV-C radiation from UV-B fluorescent lamp emissions. Differences in the inhibition of photosynthesis in the marine alga Dunaliell... - PubMed - NCBI
Edit: this indicates the initial findings from the 1987 study places an erroneous emphasis on uvb>uva. A certain high end led manufacturer claims UVA is effective and less harmful. They suggest a 3-4% of total light output in uva although publish nothing from their "research grows" to back this up.

 

[Orlando Scout]

Thanks Turbo!!! Sorry gunrack it's not a big deal. I was just trying to help out a fellow member with my personal experience. I don't know why this scientific data was brought up. He asked what we thought of uv I was just giving my personal account with uvb. Have a good day guys!!

 

[Mayne]

Hey nothing 2 more hits wont fix. If your not sellin it in a store, or entering to a cup, why the big deal?

if your not sending to a tester, *shruggs, 2 more hit will even it allllllll out, lol..

 

[PurpleGunRack]

https://doi.org/10.1111/j.1751-1097.1987.tb04757.x

UVB UVA Study Test Results Increases Medical Marijuana Potency 3-5%: UVB UVA Lighting Study Results Increases Medical Marijuana Potency 3-5%

Not much, couple of quick results from my search engine.

Removing UV-A and UV-C radiation from UV-B fluorescent lamp emissions. Differences in the inhibition of photosynthesis in the marine alga Dunaliell... - PubMed - NCBI
Edit: this indicates the initial findings from the 1987 study places an erroneous emphasis on uvb>uva. A certain high end led manufacturer claims UVA is effective and less harmful. They suggest a 3-4% of total light output in uva although publish nothing from their "research grows" to back this up.

Exactly the stuff I've seen before with an abstract based on indirect studies where no real data is presented, or the blog type ones that might as well be commercial content made by grow light pushers.

The ChilLED article is interesting, but vague and without any data supporting the claims.

A side by side grow logged here by a trusted member with harvests made into concentrate, would give us way more useful data than what I've seen dug out of google so far.

It would be easy to add reptile bulbs to most lighting systems, but we also have to *know* how to use it correctly, and if adding similar wattage of 3000K, Photo Red, Royal Blue etc. would make the same difference.
And of course the main lighting has to be taken into consderation as well, huge difference between a guy running a 400w HPS in 4x4 vs a guy running 800w LM301b in 4x4, a lot easier to improve one than the other.

 

[Mars Hydro]

T5 will be better choice. Some more expensive leds with uv, are just put the T5 tube on it. Other leds with 385 is uva, not uvb, not useful for plants.

 

[Wolf Segal]

There's a big difference between UV - A, B and C.

The 395nm is mostly if not only UV-A.



Nobody knows, it's all based general plant knowldge and on assumptions based on indicas growing at high altitudes, there is zero scientific data supporting the idea that adding UV-B will increase resin production in cannabis.

Check out the UV thread: UV lighting thread

The lamps that have UV, have it as a selling point more than anything else, so they have something special the competition doesn't have.

If I were you I'd get some 660nm in stead of chasing the UV ghost Especially if your COBs are 80 CRI

The effect of ultraviolet radiation on the accumulation of medicinal compounds in plants - PubMed

A review is given of how the production by plants of compounds useful as medicines or raw materials for manufacture of medicines is influenced by ultraviolet radiation, particularly by UV-B radiation (280-315 nm wavelength). The compounds considered in this review are flavonoids and other...

pubmed.ncbi.nlm.nih.gov