48 hours of light before harvest?

Uv radiation can definitely increase trichome production over a grow while also acting as a deterrent for pathogens like PM and even some pests, depending on the spectrum. Win, win just don’t expose your skin and wear protective glasses if working under certain types of UV. UVC light for instance has enough energy to break DNA molecules and destroy living cells, and because of this, certain companies have implemented UVC as a sterilization tool for use in hospitals, clean rooms, and water sterilization. I believe some companies use UVC as IPM for mold and mildew treatment for strawberries and cucumbers

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I think Bugbee was being dismissive of the idea of 48-hours of darkness prior to harvest. I believe he indicated tests revealed no benefit whatsoever, and he seemed to indicate that made sense, making the offhand comment that 48-hours of light might have a benefit, but there was no mechanism that benefitted growth by putting the struggling plant into darkness.

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@GreenHighland @HighTilliDie I have seen great results using a pair of Solacure Super B tubes for a few hours a day in flower, my buds are consistently frosty delicate and I’ve never seen mold or pests in the tent since using them. Definitely something for tent closed hours tho, I never go in there

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First thought is stress…cull shitty genetics if a plant goes herm.
Second thought is stretch…but what if it kicked so far into flowering, that stretch after the light deprivation was minimal?

Anyone heard of anything like this?

Yep I agree with you @Dirt_Wizard. The UVA doesn’t bother me im sure I should be wearing glasses but you definitely don’t want to be around that UVB. I checked to make sure my UVB worked after plugging up looking right at the light I turn it on and immediately im like ahh yeah my eyes burn that can be shut off. Saw a purple light bar for about 15 minutes like staring at the sun lol

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Yep, that was the interview.

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some folk use 24hr light for the last week or so to start up reveg. it is supposed to increase yield…not sure if because of reveg or because of more light…maybe both?

i think the guy from irie genetics has an episode on this. i’ve never done it.

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IME revegging plants don’t put off any significant growth for longer than a week.

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more light, more bud? that how autos work, right?

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If you’re able to reveg an “auto” at the end of its flowering time, i want to see it.

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Makes zero sense, but following nature does make sense.
They wouldn’t get 48 hrs of light or dark out in the wild so whatever.
48 hrs dark cycle only makes sense if your electricity is expensive, even then it’s just a convenient belief, and that’s what life comes down to I suppose, whatever works for you.
The stronger your belief in whatever, the more you increase chances of manifesting it in your life, it’s the law of attraction, or the law of one, whatever you wanna call it.

more light more bud. no one said to reveg an auto.

It’s the whole point of the subject buddy; for the “auto” i just commented gently your fancy analogy.

More light during half of the flowering time (over 12/12) produce more biomass, but not more flowers.


Now if you’re able to fattened your plants more than this with one week of 24/0 at the end of the flowering stage, i genuinely want to see and discuss it too.

While it’s not exactly the same given the variability in secondary metabolite production between the two plants but I think it’s worth noting that in Bulgaria where roses are grown, harvested, and prized for their essential oils they begin harvesting early in the mornings around 3 or 4 o’clock a.m. and they stop around 10 am unless it’s humid enough to continue without losing quality. They want to harvest before the dew starts to evaporate as it’s the proverbial canary in the coal mine as it relates to volatilization of essential oils. If it’s humid they harvest longer.

It makes sense that cannabis enthusiasts took this sort of rationale and applied the notion if some works then more must be better so that’s how I believe the 48 hours of darkness idea became a thing. Much love

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that is weight though. some folks just care about that.

There are some ideas about increased light schedules that are interesting. There is a breeder/podcasted I follow named Rasta Jeff (Irie genetics) who advocates for switching the light cycle to 18/6 for the last 7-10 days of flower. He claims this last boost of energy makes a measurable difference to bud size compared to a 12/12 throughout.

I’ve tried it twice (once for 6 days, once for 10) with no negative effects but in both cases it was my first and only run with the cultivar so I had no baseline to compare it too. The last round (10 days) there was a definite push and swelling in the buds in the last few days but without running it multiple times it’s hard to say if changing the light schedule was the cause. Still really interesting idea, I’ll probably continue to do it just for fun :star_struck:

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I run a perpetual set up, I’ll yank one that is ready, or very close to MY ready, by scoping the plant…
If I have a 18/6 lady ready to bust out, she gets the light, and almost ready goes to the dark waiting to be culled area.
18/6 last 7-10 days, just makes for a crazy lady, Calling nonsense on that.

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Hahaha, I’ve always been good at making the ladies crazy! :grinning:

Roots uptake water during the day and exudate at night (ever seen your plants being limp a little because theyre “sleeping”)

The idea behind the 48hrs of darkness is to let roots excrete sugars (which feeds microbiome)

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@ReikoX does something similar to this to get plants to show sex sooner. I forget the exact process but he throws em into dark for a couple days then back and they usually show sex shortly after.

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