Uvb 24/7 ???

Hello I heard on here somewhere that you can run your UVB light 24/7 during the dark period and it wouldnt cause stress.

Has anyone tried this out yet? I am curious because that would be alot of trichome production

Are UVB lights harmful in anyway to humans?

nah shouldnt be very harmful, they are just reproducing the suns effects. I know there were some old ones that they used to make that put out alot of UVA, but they quit making those. And yes UVA is harmful to humans.

Bullshit. UVB is harmful to humans and can cause problems ranging from slight sunburn to full-on skin cancer. Don't spend a lot of time exposed to it.

As fo leaving the light on the plants 24/7, it sounds like a dumb idea to me. UVB causes stress in plants, which is a good thing in small doses (from our point of view, anyway), but too much stress will quickly lead to hermies and/or dead plants.

UVB is not known to cause any more serious stress to plants than the sun would. BUT TO STAY ON TOPIC

I have also heard that you can train your plants into running the UVB 24/7 regardless of cycle. I would start running it 6 hours during light, and then add an hour every day. So after 14 days it has slowly been introduced to keeping a UVB bulb on 24/7... Now I haven't personally tried this- but it seems it would be a fairly reliable method in introducing UVB to your plants 24/7

Also, I would recommend a remote control lightswitch so you can turn the UVB bulbs off prior to entering the grow room, which will prevent any of the UVB light from ever touching you, making it 100% human-safe to use.

Hope that helps.

Anyone got any links to grows where UVB has been used 24/7? I'm still not convinced personally, although I am far from an expert.

I have seen stress caused simply by leaving a 10.0 UVB bulb on 12/12, so 24/0 seems like total overkill to me, as well as being very unnatural. Maybe a 2.0 or 5.0 would be better for this, but it still doesn't seem right to me to have it on in the dark period.

I can't say 24/7 but a study conducted in 1986 used UVB for only a few hours, and it showed that the increase of THC in trichomes was in linear proportion to the additional exposure of UVB.

UVB can cause blindness. When I get ready to run UVB, I'm gong to enter my room with UV-blocking sunglasses and probably sunscreen. I'm not going to bother turning it off.

Why is everyone doing the same thing with UVB as every thing else acting like we each know it all...
The generic "stress, but too mcuh stress...." response
"I haven't tried this, but"...
Just say I don't know or look it up no more trite bullshit.

If you grow outdoors, your plant flowers due to the diminshing of the directness and amount of light reaching your plant. UVB exposure reaches apex in veg and tapers off throughout flowering (just like the rest of the sun)...

at harvest time on my latitude I receive less than an hour (30th parallel[semi-tropical]) over 150 microwatts uvb per day, that is nothing. You should calculate 250uW from your light, find the distance from the bulb that that is and imitate sunlight for best results
In my experience, you can do a little more than the sun but you will start seeing spotting in your leaves and shit.

If someone has better luck doing multiple exposures per photoperiod, I am ALL EARS!!! I'd love to run some experiments with this bulb but as for now I am sticking with sun imitation, it has worked with the most success (Ive tried multiple exposures/photoperiod and I always have problems)


nycd day 37

8deez8 said:

Why is everyone doing the same thing with UVB as every thing else acting like we each know it all...
The generic "stress, but too mcuh stress...." response
"I haven't tried this, but"...
Just say I don't know or look it up no more trite bullshit.

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The reason that the "stress but not too much" is considered a generic response is because it holds true in 99% of cases, and your post simply backs that up.

Also, just because Growtech (or myself) haven't tried this, are you saying that our viewpoints are invalid? If so, I should point out that you haven't tried 24/0 UVB either.

I have never stuck my hand into a flame either, but reading accounts of others who have is enough to convince me that it hurts like hell.

Like I said, never tried this- but I can't say if it will or will not work. Only recommending that you slowly adjust the amount of exposure to your plants hopefully preventing any shock they might deal with.

turn it on 24/0 and your plants will droop, turn a bluish hue, and become crispy/brittle
uvb stress will not cause hermies.

yea, if you've no experience I say pretty clsoe to invalid, esp with such trite info. just trying to minimize the clutter people have to read thru. I don't know why some of you are on here but this is strictly an info site for me and I hate having to read through people who are just trrying to get rep and friends (not that you are!). hope im not offending anyone.

Leave it on too long, with not enough intensity, you are not doing it properly and will notice. (however for the lazy this is the way to go, but never more than 10 hours/photoperiod)
Have it too close, you are not doing it properly and will notice. (spotting of leaves near veins, sometimes black spots, sometimes blue leaves that are crispy)

BUT

If you start in mid/late veg, with 200-250uW/f2 UVB for <8hours mid photoperiod, and taper off, week by week, until you are minimally using (<1hr) it in late flower, you have imitated the sun and are doing it the best way I have found! This will take substantial time off of your flower period, no shit. I am confident the reason many indoor growers have (maddeningly frustrating) extended flower periods is lack of UVB... I have not tested w. w.out so I don't know exactly how long, but noticable.

I will continue experimenting, but I am confident by adhering to the sun's schedule as best we can (intensifying it of course) we can push the plants potential to tha max

My next grow I will be using UVB from week 2 from seed. marginally at week 2 of course... but building it up to late veg and backing it off starting before flower.

remember, MJ flowers when sunlight has decreased intensity, and is only available -+12hours

8deez8 said:

turn it on 24/0 and your plants will droop, turn a bluish hue, and become crispy/brittle
uvb stress will not cause hermies.

yea, if you've no experience I say pretty clsoe to invalid, esp with such trite info. just trying to minimize the clutter people have to read thru. I don't know why some of you are on here but this is strictly an info site for me and I hate having to read through people who are just trrying to get rep and friends (not that you are!). hope im not offending anyone.

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I have read accounts of several grows where the grower was convinced that the addition of too much UVB was the cause of hermies, and since all other environmental factors were the same, and the clones came from the same mothers as previous, hermie-free grows, I would say that their assumptions were pretty reasonable.

Have you ever though that maybe you were just lucky in growing some pretty stress-resistant genetics? Some growers can grow for years without ever seeing a hermie, while others with virtually identical environments can be plagued with them.

I personally have never had a hermie that I thought was linked to UVB, but I have seen enough evidence to convince me that it is a real possibility.

Also, I will point out again that you have not tried 24/0 UVB yourself, so your opinion is just as invalid as you perceive everyone else's to be. (ie: not at all, since this is a discussion forum).

Your viewpoint is just as trite and generic btw. Imitating the sun is a good starting point, but there is always room for experimentation.

It would make sense UVB would cause hermaphrodites, as ultraviolet radiation is known to cause mutation. That's how we get skin cancer from UV exposure.

Nocturn3 said:

Your viewpoint is just as trite and generic btw. Imitating the sun is a good starting point, but there is always room for experimentation.

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As far as I can tell, I'm the first on here to use most intense uvb in veg, and backing off in start of flower.

"My next grow I will be using UVB from week 2 from seed. marginally at week 2 of course... but building it up to late veg and backing it off starting before flower."

"I will continue experimenting, but I am confident by adhering to the sun's schedule as best we can (intensifying it of course) we can push the plants potential to tha max"

I just meant that future experiments may benefit from this:
I have had success with the following:
use equatorial level UVB radiation (~250uW),
have mid-length (<5hr) uvb photoperiod in mid veg (as soon as root system is est)
have longest (<7hr) uvb photoperiod in late veg/first week of flower
have mid-length (<5hr) uvb photoperiod early flower, and taper off until you use little to none as they amber to your choosing.

Flowers form quicker and harvest comes quicker,
and not to be a smart ass but ive read uva causes hermie and skin cancer, not uvb. i allow the hair splitting in this case to try to illuminate the fact that everyone confuses/pretty much RAPES the two on here.

Nocturn3 said:

Also, I will point out again that you have not tried 24/0 UVB yourself

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yea you've said that twice now...

I tried 24/0 in veg, and here's what happened. (as i said in my last post)
"turn it on 24/0 and your plants will droop, turn a bluish hue, and become crispy/brittle"

Im not making that up but apparently im wasting my time

Nocturn3 said:

Bullshit. UVB is harmful to humans and can cause problems ranging from slight sunburn to full-on skin cancer.

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actually 14pimp was right there... Uva is the only kind that even penetrates the outermost layer of skin,
had I seen what an idiot you were earlier, I wouldnt have wasted my time.
you don't have a clue what you're talking about

GrowTech said:

BUT TO STAY ON TOPIC

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keep trying growtech...but it's idiots like this that make this enjoyable hobby painstaking.

8deez8 said:

and not to be a smart ass but ive read uva causes hermie and skin cancer, not uvb. i allow the hair splitting in this case to try to illuminate the fact that everyone confuses/pretty much RAPES the two on here.

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Not true at all, so you've no need to worry about being a smart ass.

http://info.cancerresearchuk.org/news/archive/newsarchive/2008/july/18670669

http://en.wikipedia.org/wiki/Ultraviolet#Harmful_effects

Edit to add: Maybe before you go around accusing people of not having a clue, you should actually research what you are talking about.

8deez8 said:

actually 14pimp was right there... Uva is the only kind that even penetrates the outermost layer of skin,
had I seen what an idiot you were earlier, I wouldnt have wasted my time.
you don't have a clue what you're talking about

keep trying growtech...but it's idiots like this that make this enjoyable hobby painstaking.

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Plus it should be considered that tanning bulbs run a healthy dose of UV's. It takes quite a but if exposure to get cancer. The UV level in Las Vegas for example is 7 today in Cali anywhere from 5 to 9 depending on where.

That means a single 7.0 UVB isn't going to give you cancer. You would have to live under the damn thing. Unless you were already destined to get skin cancer.

Think about all the leather-women who have baseball gloves for faces, and no cancer.

Not everyone lives in vegas or cali, and some skin types are far more susceptible than others. Playing down the risks is not a good idea. Your skin may be accustomed to UV exposure, but it doesn't mean everyone's is. It doesn't mean they are "destined" to get cancer, just that they have an increased risk factor.

Nocturn3 said:

Not everyone lives in vegas or cali, and some skin types are far more susceptible than others. Playing down the risks is not a good idea. Your skin may be accustomed to UV exposure, but it doesn't mean everyone's is. It doesn't mean they are "destined" to get cancer, just that they have an increased risk factor.

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There were over 1600 deaths in Australia from UV related skin cancer in 2005, not to mention the other half a million people here who have them removed every year, it is very dangerous and it's no wonder plants react to it.

just dont replace ur standard bulbs with uvbs and ur good..some people think its sooo bad but the rays are to weak and were only in the grow room for a little while at a time at least i am..but back to topic i heard about my boy runnin uvb 24/0 and it wouldnt stay at a flower so i'd say no dont run uvb 24/0 not even in veg..at least not to much and not to close..one reason y i wouldnt run my uvb that long is becasue uvb makes ur plants use their nitrogen faster so to much uvb will make ur plants go yellow..i got 4 uvb's in my grow room and there on 10-12 hours a day