Black light during lights off?

A friend just recommended that I should run a black light for my autos during the 4 hours of lights off time. I am new to growing and tried researching it and seen some information about UV lights. Is that the same as a black light? Also is this recommended or beneficial for autoflower plants? Ive been given some pretty folklore advice about growing before from this friend. Im not saying thats the case here, but I wanted to seek advice on it before doing it. Thanks

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What @Blastfact is saying is true. Uvb light is strong and can and will burn your plants easily and should come on for the last half hour of your light cycle during the last few weeks of flower. Uva light is easier on your plants and will benefit by being on while your flowering lights are on from week 3 of flowering till the end.

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No benefit of doing it at lights out really.
If it was photos then absolutely not as it is light period.
But if its autos then it shouldn’t hurt them but theres no reason to run it at night and while black lights can sometimes have some uv, its not enough to do anything fir them.
Now I am on the side of uv at minimum helps pull color out as i ran an experiment last year with a some purple cookies clones and the one under uv was dam near black it was so purple and the others grew with no uv had just a tiny bit if color.
Some claim it increases terps and potency but i saw no difference in these areas with my one amateur experiment.
They was absolute fire though from the start so mabe the pheno was pushing max levels anyway, it very well could pull a 20%thc over 25% but if its pushing 30% all ready it may not go any higher :man_shrugging:

So add uv with the regular light schedule if you want to but i don’t believe a bkack light is worth running at any point from the videos I’ve seen talking about good uv sources…

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You will of course need to put some research into the lights you get just like you would for researching main lights so you get ones of the correct power levels to have a positive effect

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Kind of defeats the purpose of lights “ off “ doesn’t it .

:thinking:

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In my research plants respond to UVA light by producing more Trichomes and essential oils.

Crops planted in the Hindu Kush mountains of Afghanistan and at the Pineapple Kush farm in the mountains of Northern California are higher up and more UVA energy hits them than at lower elevations.

HYPHOTONFLUX UV-A LED Grow Light, Commercial UV Supplemental Bar 30W, Two Pack

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HLG has their 30 watt uva on sale for about $95.00 now.
Maybe it just me, but I would rather buy from them than Amazon.
I know both lights are made in China. But I think that HLG has better quality control than a lot of the Amazon suppliers.

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That wouldn’t be biased would it? Have you purchased/used a HYPHOTONFLUX product?


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I think I saw HLG all over Amazon.

Here’s the HYPHOTONFLUX website.

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I’m sure your friend was well-intentioned, but this is pure broscience, growmie.

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It is like this. Just about everything in my grow rooms have made in China on it. So when I am buying a product, and can find equal price and quality from a USA company. I am going to give the USA company a little cut of the profit every time. So yes, I am bias!
I know that HLG & GGM sell on Amazon. But when I order from either of them I go directly too their websites, and receive great customer service.
No I have never used that brand name product. I did follow the link that you provided, and looked at the business address. I will leave it at that. But are correct I don’t know about their quality. I did not call them out by name, but I admit it came close.
BTW are you drying your buds in as much light as it appears in the picture?

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He was claiming it simulates the uv that plants in nature get from moon light. ill admit that I know very little about this kind of thing so it seemed at least plausible to me. But as i said he also told me to dry with root ball on plant which I read is not a good idea at all. I still have a lot to learn about growing for sure and I have discovered that there are many practices and techniques that some swear by while others denounce. Its been complicated, confusing, insightful and over all fun so far. Next piece of advice I have to research is if i should give plant roots an ice bath during flushing :flushed: lmao

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Flushing is technically not necessary, which I know to some growers is insane to even say. But just think about it. Flushing and fading isn’t even a recognized technique for any commercially important agricultural crop, including tobacco which arguably focuses more on flavor than cannabis. And don’t get me started about the “you’re smoking the nutrients” discussion.

The ice thing, again. There’s absolutely no science behind it. Just another method invented by black market growers that still proliferates as a necessary step for some reason.

But I mean, hey. If it makes you or any grower happy I say go for it. Worst thing that can happen is you make more work for yourself or it doesn’t work.

I’m just a big advocate of the “less is more” approach and I have to admit that I still have to curb my enthusiasm to touch my plants and try new things. I also like to be honest with people though, I wanna see my fellow growmies succeed, so I like to cut through the broscience as much as possible and help kill a lot of these age old wives tales that confuse new growers.

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ive kept it pretty simple this grow since its my first and I dont want to just goof it up above all else. As time passes and i have more experience Imay start micro managing more. mostly just for an excuse to play with the plants lmao. I am after all a hobby grower since I cant even partake in my bounty. (damn randoms) i have actually been really surprised by how much ive been enjoying growing

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At least half, if not most, of the fun with growing my own is the growing itself – I love watching seeds and clones become big smelly monstrocities. I can def relate!

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Just chopping them from my 4x4 auto tent next to the 9x4 where my photos are. They went back the 4x4 by EOD.

I just wish HLG would get a Bar style fixture that you can move the driver outside the tent.

Removing some heat from the diodes kinda extends the life and performance.

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So with UV and Far Red on separate circuits or is it the dimming feature?
I suppose which HLG are you comparing to? Some of use can’t spend twice as much to get the branded product that some influencer pulls specs OTA.
Here’s the specs on the HPF4000(2) I’ve been using for a couple years now.
TOP QUALITY COMPONENTS & HIGH OUTPUT — Equipped with market leader Samsung LM301B & Osram deep red diodes (total 1,272 pcs), HPF4000 draws 480 watts, powered by MEANWELL driver, it delivers PPF Efficacy up to 2.7 μmol/J and an average PPFD 1300 μmol/s @12" in 4’x4’ coverage, harvest 2.5g/w easily!

The link I sent for the 2022 Pro480
HIGH EFFICIENCY & TOP COMPONENTS — HYPHOTONFLUX 2022 Newest PRO-480 LED grow light is built with SAMSUNG LM281B+Pro Top bin diodes. 480-watt power draw delivers 1250μmol/s light output and achieves 2.6 μmol/J efficacy.

Which HLG are you basing your comparison?

I think HLG claims 3.11 μmol/J on the 350 at 330-watts.

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I like your brand loyalty!
But when you are ready to buy a new light. Do yourself a favor, and call HLG. Tell them what your have in terms of tent sizes, and where you want to go with the purchase. I am sure the results of this will cause you to spread the loyalty around some.
With their build your own kits can customize to your layout, and save some money on a quality light.
BTW, that is a lot of tent to light up that you have.

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I have all three of my drivers remote mounted. Two were factory built, and the other is a HLG kit, (Diablo). Great way to do it, and makes getting to the dimmer screws much easier. Provided that you have a good place to mount them.

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That sounds like a really nice setup.
My buddy got the HLG 350. I had to try the HYPHOTONFLUX HPF4000. I added another one last year along with supplemental lighting Far Red and UVA.

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