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Turn down my lights for final two weeks?

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Tom1974
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Turn down my lights for final two weeks?

Post by Tom1974 »

Running 3 x Telos pro 10 mesh LEDs in my space and wondering if I should reduce the light output from 100% to 75% now for the final two weeks?

Just a thought that crossed my mind due to not wanting to overdo them and all the lovely crystals so close to the end :-)

Cheers guys

Tom
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Re: Turn down my lights for final two weeks?

Post by wutang »

This is maybe Wu Science (aka bro science) - why would you though? If they've been doing well under the same amount of light? I never have...I'm sure some others may come into help. Goodluck with the harvest
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Re: Turn down my lights for final two weeks?

Post by Tom1974 »

wutang wrote:This is maybe Wu Science (aka bro science) - why would you though? If they've been doing well under the same amount of light? I never have...I'm sure some others may come into help. Goodluck with the harvest
Just what “some guy” was advising down the hydro shop yesterday when I went for my flush

He said you don’t wanna damage any trichomes or THC at this stage so reduce the lights now

Had a feeling it was a bit “bro-sciency” and knew this place would be the place to ask before doing so

Cheers buddy
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Re: Turn down my lights for final two weeks?

Post by Hmr81 »

Nah man, i'm not buying that lol. I'd leave it to ride out as it is mate.
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Re: Turn down my lights for final two weeks?

Post by ncrypta.core »

Not my work but

As ripening phase progresses, natural senescence will begin to set in and the stored chlorophyll will begin to degrade, revealing other pigments within the leaves such as anthocyanins and carotenoids in a sea of purples, oranges yellow and reds.
This happens as a natural part of the plants lifele as a means of controlling the lifespan of the plant.
As this chlorophyll breaks down, the photsythetic rate of your plants is decreasing. As a result, we no longer need to high intensity levels of light to fuel biological growth.
Not only have we begun to reduce the nutrient strength of our irrigation solution, we can also begin to ramp down our ppfd which will help minimize the evaporation of some of those volatile compounds as they continue to produce and accumulate in your flower during this last critical stage.
Even though photosynthesis has slowed, your plants are still producing compounds, and swelling in density using the remaining photosynthic capabilities of the plant, as well as stored energy withing the leaves itself.
Be sure to be mindful of the environmental impacts lowering light intesity may have on your space such as cooler temperatures and higher RH% *At this stage we are looking to keep our rh% low with a higher vpd to mitigate moisture issues that could lead to catastrophic results.

For me
Week 1-5: 1100-1300
Week 6-8: 900
Week 9+: 700-750 ppfd
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Re: Turn down my lights for final two weeks?

Post by Keeno »

I've been doing exactly this for some time, especially im the cooler months. Someone once said to me that every time you open your tent and are hit but thst wall of smell it's the terpens that are being burnt off by the environment.

That to me meant if I could somehow slow this process I'd have more flavour and aroma left on my plants when I harvest them.

So I started lowering lights a little, dropping temps where I could. It certainly worked. Strains I'd grown from clone were better, had more delicate smells, this in my head could only be the preservation of more delicate terpenes on the plant.

All bro science from me, but I'd say cooler temps and less light (but still enough of it), can only be beneficial in the later stages of flower. That being said, as ncrypta.core points out, you do not want high humidity in late flower. So it's not always easy to do it. In the winter months I find humidity low anyway so I'm able to really push the theory. In warmer more humid months I'll stick with what makes high humidity not a problem.
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Re: Turn down my lights for final two weeks?

Post by fabi420 »

Here in Germany/Austria we have a very large and well-known lamp manufacturer (SanLight) who recommends exactly that. The reasons are those Keeno already listed. The final development of the terpenes and the ingredients is said to be better if you turn the light output down towards the end. The exact scientific findings are all in German and only in one video, so unfortunately I can't explain them to you exactly. But I can tell you that it's not bro-science anymore. 😎
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Re: Turn down my lights for final two weeks?

Post by 2-Scoops »

They can and do pack on up to a 3rd of their final weight in those final 2 or 3 weeks so why would ya wanna do that. Doing it does or can indicate to plant end of days is close though as your trying to mimic outdoor conditions towards end of their life when theirs less light for the plants outdoors so they'll hopefully produce a bit more resin in process of finishing up a little quicker, but really what's point doing it indoors when you`ve created ideal conditions, the plant is still gonna finish up nicely but you`ll have a bit more stinky buddage. You will get same effect swapping light out to a more blue spectrum or raising light a few inches as well, but again what's point, i mean these are all things that I've tried myself once upon a time to try and produce more sticky goodness on my buddage, but nah man its a right load of doo-dah this one and if does do anything its nothing of any noticeable difference in my opinion. :shit:

If your wanting to add more sticky goodness to your buds towards end of a grow stick a t-5 > uvb light (290-320nm) in your room set about 9 or 10inches above your canopy for last 2 or 3 weeks for ten hours daily during your daytime hours that's pretty much proven to work these days and you`ll still have shed loads of buddage 8-)
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Re: Turn down my lights for final two weeks?

Post by Dex »

Interesting for me I make sure temps doesn't exceed 24c-26c with lights on and I do change timer towards last weeks to rather than 12 12 I drop to 11on/13 off or 10on/14off

My science is more or less temps play big role on terp production of terps and flavours as well as showing the plant that time is near and accelerate the process.

But what above I do like what I'm reading on the light power playing a role so this has been educational question lol and I'm loving the reply
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Re: Turn down my lights for final two weeks?

Post by MommaB »

Oh this is interesting I’ve heard people doing lights off for a few days before harvest I’ve seen all sorts of bro science things but I will say it does make sense to me.
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