Why go 24 hours lights on??

[JJScorpio]

I might chime in here.

I'm no scientist. But I have done dozens of grows, both with 24 hr lights on vegging and 18/6. It's my findings the ones vegging 18/6 were just as big, and in my opinion healther than the plants grown under 24 hour light.

Do I know why? No. Do I care? No..........

 

[spurr]

I know very well whom Bob Smith's pseudonym is...

I really hope you don't know who I am or I need to change my VPN ASAP.

I'm really puzzled and beguiled that you've sent me two PMs asking about my "other user names" - I only have one name, just "Bob Smith" (not my real name, in case that's not clear).

And this is me being sincere (for the umpteenth time) and telling you that I'm curious to hear your answer on this issue (as Zero appears to have some interest as well) - if you don't want to answer me, then at least answer the others on this thread who might also be interested in your answer.

Look up what "pseudonym" means...<sigh>

A tip for you: a VPN offers little real anonymity. I will help you in this regard: look into Tor, the best anonymity short of your own bot network...

FWIW, it's your sarcasm and adversarial attitude that stops me from wanting to answer any of your questions. I will not be 'forced' into anything, especially helping someone I choose not to help.

Finally, I'm sorry if you find my skepticism "adversarial" - I analyze things and call it like I see it - you've not presented (to me, anyways) any evidence that your hypothesis is any more valid than anyone else's thoughts on the matter who has not tested their hypothesis.

I understated that is what you think, and that is why I feel no need to try and help you. I know you couldn't care less about the sound, proven scientific theories I have presented. And I know you couldn't care less about what I have to write. And once again, I am not using a hypothesis in terms my, and others, main claims: (1) that a plant benefits from a dark cycle; (2) that plants grow the most at night and very early morning; (3) and that it's DLI that matters, not hours of light per day.

Your continual insults and sarcasm really don't make me want to help you. And for the umpteenth time: a laypersons definition of "theory" is synonymous with "hypothesis"; but "scientific theory" is not synonymous with "hypothesis".

Bob, just give up. I will not answer any of your questions because I do not believe you are sincere. And if you are sincere, you have already shown you couldn't care less what I have to write, so why should I bother? (that's a rhetorical question, no need for you to answer).

I am not asking you for anything, please, just do me the same courtesy.

 

[GeorgeSmiley]

Hey real quick, when giving vegging plants a dark period, does it have to be complete darkness for the plant to take advantage or just reduced light? Like I switch off the t5's above the plants but the tubes on the ceiling are still on. Is there a threshold?

Thanks
Smiley

 

[VerdantGreen]

hey George, im pretty sure that it doesnt have to be totally dark to facilitate the plants light independent functions. probably be better if your overhead lights were cool white (more blue) than warm white.

i sure someone will correct me if im wrong

VG

 

[Thomkal Vwalaa]

hey George, im pretty sure that it doesnt have to be totally dark to facilitate the plants light independent functions. probably be better if your overhead lights were cool white (more blue) than warm white.

i sure someone will correct me if im wrong

not to mention the spectrum control available with those newer LED lights.

now will you guys kiss and make up? we all got weed to grow.

 

[bobman]

Wow, I think we are in RUSSIA. Heavy edit of posts. Somebody has a serious complex. Bob changing avatar back.

 

[JJScorpio]

The posts were removed because they were rude and argumentative......

Regarding my earlier post, I grow in soil with a pair of 600 watt HID's.....

I think in truth there's very little difference in which way you choose to go........ So why is it worth all this arguing?

 

[bobman]

I agree. I just run real tight cycles so every inch counts (thats what she said). I have done side by side grow of t-5's and t-8's and 1000 watt and noticed a huge difference. And I have done hempy vs soil and also noticed a huge difference. I just do not want to miss out on growth but I am dying to save some power.

 

[bobman]

I also did big clones vs small clones and noticed a difference for the first couple of weeks but after that they end they all evened out.

 

[bobman]

From doing reading and observations on mine own I would probably have to say that for rooted cuttings 24/0 for 4-6 weeks will probably grow plants quickest. After that 18/6 or 20/4 or 24/0 may not make a difference.

 

[VerdantGreen]

for crying out loud Bob Smith please do not post in this thread again. for the second time you have deleted all your posts - which confuses the thread.

although having said that, even with all your posts deleted your positive contribution to the discussion remains the same.

the ony post of yours that was deleted by mods was the one where you posted the contents of a Private Message in the public forum - which is clearly against the TOU

you are a total waste of time.

VG

 

[spurr]

hey George, im pretty sure that it doesnt have to be totally dark to facilitate the plants light independent functions. probably be better if your overhead lights were cool white (more blue) than warm white.

i sure someone will correct me if im wrong

VG

You are correct, the key is the light intensity. And yup, lacking of far-red light is a good idea in terms of Pfr (aka PhytoB) accumulation.

 

[TriWingGirl]

Having had some time to experiment i have discovered that they grow faster with 2-4 hours of no light and some time to sleep.

Thank You so much it was this discussion and the varied opinions that caused me to experiment and discover that 18/6 is not the best timing cycle for the fastest growth. A better cycle is 20/4. 24/0 is not so good either it has a tendency to yellow the leaves and slow the growth after awhile. they need some dark time to grow, everything needs a little sleep.

All you have to do is put something in some dirt, put it under a light and observe.

Good luck everyone I got my answer Thank you

 

[Thomkal Vwalaa]

The posts were removed because they were rude and argumentative......

Regarding my earlier post, I grow in soil with a pair of 600 watt HID's.....

I think in truth there's very little difference in which way you choose to go........ So why is it worth all this arguing?

No comment.

Hey, I grow much the same .

BUT I would have to disagree with the last statement. It is all worth arguing (in a respectful manner). That is part of science. For too long we have taken the traditions as facts. 18/6 and 12/12 is not ideal, and we need to discuss it... politely and without taking offense when others do not agree.

And as this is not the 'science only' forum I'll say that over the past 10 years 20/4 veg has worked out best. 24/0 is dangerous. 18/6 is limiting, but perfectly fine, especially for mother plants.

 

[macdiesel]

Sooooooo....lets stir the pot a bit.

If you can get a female to flower with 15/9, would that be better than 12/12?

More light my friends......

 

[Thomkal Vwalaa]

Sooooooo....lets stir the pot a bit.

If you can get a female to flower with 15/9, would that be better than 12/12?

More light my friends......

That would depend on your definition of better. Also: does flowering take longer?

 

[VerdantGreen]

that's a whole different topic - and there is a thread about it here

https://www.icmag.com/ic/showthread.php?t=190023

VG

 

[DirtDoctor]

Tell me one thing you are going to change or do in your garden based on the info.

Nothin' Bud, I already veg under 18-6 with thoueys. Thanks for your concern!

 

[DHF]

........

 

[Frozenguy]

Nope, plant rate of photosynthesis is reduced after about the 17th-18th hour of non-stop light. At that point much of the active rubisco has been converted into inactive rubisco, which means the plants can't keep up high rate of photosynthesis, because rubisco activase is less able to 'do it's job' under 24/0. Also under 24/0 C assimilate/partitioning goes down past the 17th-18th hours, as well as Co2 fixation, etc.

You described it well when you wrote about how plants need to 'switch' modes (excuse my simple description) to carry out light independent reactions such as starch conversion, cellular repair, etc., if light is provided 24/0. Plants simply can't use light to photosynthesize and carry out other needed reactions simultaneously, and keep up a high rate of photosynthesis.

So, do we know, at what rate the plant is photosynthesizing after about 18 hours; and for how long this reduced rate is sustained?
I have to assume its substantially reduced.. One would have to know the rate, roughly, if one were to attempt to test this.

This topic is also why using Co2 over ~1,200 ppm is bad, as well as temps over ~89'F. In both instances the amount of rubisco activase is reduced, thus the plant is less able to convert inactive rubisco into active rubisco. That means the rate of photosynthesis goes way down and the plant suffers (just like if using 24/0 of light). I have a few studies on cananbis that looked at ideal level of Co2, along with PPFD and temp, all found Co2 saturation at ~> 1,000 ppm, just like most other C3 plants. Thus using more than 1,000 ppm is a waste, and using more than 1,200 ppm can/does hinder rate of photosynthesis due to reduction of rubisco activase. That is another area of BS in the cannabis world, i.e. claims that 1,500 ppm of Co2 is ideal (that has never been proven, it's only more conjecture and anecdotal evidence from 'first hand experience' so loved by some in this thread). Check out this thread for more info I wrote on that topic: "A simple question for growers that use CO2"

"Robust Plants' Secret? Rubisco Activase!"
Steven J. Crafts-Brander and Micheal E. Salvucci
Agricultural Research Magazine, Nov. 2002, Vol. 50, No. 11
http://www.ars.usda.gov/is/ar/archiv.../plant1102.htm

I usually run at about 92F when applying CO2, just what I've found best from 88,92, 95, 97.. Maybe I should of tried 90 hah.. But I also read this in that link

Denaturing of rubisco activase can occur at temperatures as low as 89.6°F. But rubisco continues to function effectively until temperatures reach 131°F, Crafts-Brandner and Salvucci found.