Changed my light schedule and way easier to sex and grow way quicker. 18-6 is almost 2 days worth of light. The one hour on keeps them from going into flower. Any input is appreciated. I’d like more options about it. High times lied so we would get busted and grow mids lol
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Ive heard of alternate light schedules than the most common - 12/12 and 18/6, but it does seem to have a lot to do with simplicity.
Like you mention, ive heard of interrupting the dark period with about an hour of light, but I’ve never tried…
Id love to hear more about it!
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I run 16-8 for veg and 11-13 for flower. 11-13 schedule I’ve noticed plants finish 3-5 days faster, sometimes 7 days earlier.
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I think @GrownAtHighAltitude has experience with different lighting schedules.
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My understanding is that the plant can only photosynthesis around 9 hours of light so 9 more is stressing them big time. Not saying that it’s correct but it’s my understanding I’m willing always to learn more. But I run the 12-5-1/2 and it’s night and day. I believe they grow in the dark not when 1000 watt hps is in it 
. Plike I said don’t hesitate to correct me there’s so much bro science I don’t know what to believe. But it comes from old greenhouse growing back in the day. I heard blame the Dutch jk lol
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I’ve never tried the gas lantern technique, with interruption during the dark period, but I often run 18/6 for seedlings, then gradually drop the hours in forst week upt to flower, until eventually leaving it at 11/13, or even 10/14 because electricity aint cheap any more haha.
I’ve heard the gas lantern method does well keeping the plants in veg, and they generally won’t show sex, or show it very little until you put them into flower.
But once you do flower them, they really take off!
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The way I understand it, the veg and flower light cycles that we’re so used to hearing about, most likely stem from simplicity and not really from a lot of science.
Understanding how much light your plant needs and can actually use is easier to figure out if you have a DLI (daily light integral) chart and know the ppfd of your light. As well as knowing a bit about Vapour Pressure Deficit (VPD) as well.
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Gas lantern tech I have to check that out I know with the one hour of a led they will show pretty quick I’ve ran a few runs using it in veg and stopped getting all the bs issues that pop up now and again. But 18 hours on would be about 2 days worth of light compared to outside. Or have I went down the rabbit hole and got lost 
Lol
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I’m pretty sure joe Pietri talks about cycles like in this video at about 52:50 in.
I’ve seen a buddy use this lighting cycle and do very well.
Peace!
Edit: Here is what my friend on another forum posted about this topic
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Yup I believe it’s him he has a website www.growwithjoe.com I believe and his books are expensive like 500$ but I found a few others that run the schedule also. Thanks for that info much appreciated
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Yup and some love the idea some say I’m full of it. The flower I run 9 on seems to be a sweet spot
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Not sure if I totally agree with the 6hrs on during flower, again I think that will just depend more on the intensity of your light and spectrum.
If you’re only hitting 800ppfd for 6hrs vs 1400 for 6hrs, that’s a big difference in how much light the plant is actually receiving.
@Blueridge the 12 on, 5.5 off, 1 on, 5.5 off is the gas lantern technique.
Name comes from when growers would light a gas lantern during dark periods to trick the plants into thinking it was day time again. And prevent them from flowering.
When the plants receive the right amount of time without light they trigger and begin flowering, this starts a process in the plant which reduces Auxin production and start to increase the production of other hormones responsible for stretch and flowering.
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That’s what I was thinking probably would do 8 hours or 9 maybe in my own garden once I give this “latern technique” a shot.
Personally using an HLG Scorpion Diablo Quantum Board style LED, but I’m sure like you mentioned that light intensity at the canopy is probably a factor that would need more or less light hours in flower while using this approach.
Great conversation y’all, I love learning about things like this to try out next cycle or another one very soon!
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One guy on Instagram did 6 hours and wasn’t the prettiest but not to bad I’ve seen worse and done it myself lol
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9 is supposed to be all the stigmata can take . Not sure if stigmata is the right answer but what absorbs the light
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the gas lantern is underrated.
have run in it for these things.
-vegging at night (hot climate) save $
-vegging seedlings (+esp clones) in spring to avoid reveg outdoors
-keeping plants smaller in veg (avoid up-pot/conserve space/keep mom)
it should also ease transition to flower, since you’re just removing the interrupting hour.
i don’t think you need to use a full hour at full PAR, or place it absolutely in the middle of the dark period, but i always did, as i didn’t wanna get too cute/clever for no good reason.
i don’t use it exclusively, as situations and plants differ so much, but in general i’ve had no issues with anything
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When you guys say gas lantern do you mean a actual lantern?
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No, that’s just the name given to the technique, as farmers used to use gas lanterns I their greenhouses/tunnels etc.
It can be pretty much any kind light to be honest, all you’re really doing is interrupting the consecutive hours of darkness with a little burst of light to prevent them from producing the hormones they use to flower.
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I hear you! Electricity prices are absolutely insane right now, the UK especially is a joke. Our energy costs have quadrupled over the last 2 years.
I have my current set up on 18/6 but run it so so the lights are on at night, keeps temps stable throughout the whole grow.
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I ran 12/1 and 8/16 exclusively for 2 or 3 years. With most cultivars it worked great. Faster finishing same yields and quality were what I experienced for 99% of the plants.
The Taos OG clone showed wild growth under the veg routine though, the internodal length shrunk to almost nothing, like 1/4 inch and trichomes developed too. Then when transplanted outside, it created too many bud sites which didn’t fully develop into large buds like I expected, mainly in the lower parts of the branches. This was really the only clone that this happened to. I had a couple of other seeds that started flowering early under the 12/1 schedule but that was it. Everything else, probably 2 dozen different cultivars tested were fine.
I have since moved back to 18/6 and 12/12 since I have a lot of old cuts now but it would be interesting to see what happens with those. I wonder if really stretchy cuts like Triangle Kush would tighten up a little also.
A commercial shop would be wise to test a room with their cultivars and see for themselves because the electrical economic advantage is no joke. 30 to 40% savings.
I got it from Pietri but I don’t like that guy otherwise and the information is in the Greenhouse Management textbook. I bought a used copy of an older edition to verify.
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