New Grower Growing autos under 24 hr lights?

Thanks for the replies everyone.

I was a bit stoned at the time and was careless to post sources as to my reasoning behind telling the OP to do 20/4 instead of 24/0. My fault guys.

Some quick sources -

1. Biology lesson.
2. When do plants grow faster? Day/Night?
3. Biologists discover an 'evening' protein complex that regulates plant growth

My personal preference and testing has shown me that my plants do grow faster when having a 4 hour dark-period. Many others may, or may not agree with me. Try it out for yourself.

If you do a simple google search in relation to which light cycle is better you'll find countless threads of people debating it. From what I've gathered 20/4 is the majority, but that's not saying that 24/0 cannot be effective, or isn't effective. I just highly recommend 20/4.


Please see above post.

it hasnt been proven that autos need a night period.

"While most people assume that plants grow at a slow and steady rate throughout the day and night, Charles Darwin and others more than a century ago observed that they actually grow in spurts late at night, with plant stems elongating fastest in the hours just before dawn."

"More importantly, the biologists show how this protein complex is intricately coordinated through the biological clock with the genes that promote stem elongation in a way that could enable plant breeders to engineer new varieties of crops that grow faster, produce greater yields of food or generate more biomass per acre of land for conversion into biofuels."

"Because the three genes -- Early Flowering3 (or ELF3), ELF4 and LUX -- have biological activities that peak in the early evening, the UCSD biologists wondered if the three genes acted together in a protein complex. Through a series of experiments in yeast cells, they determined the three genes produced proteins that did interact with one another, but in a specific way. ELF3 served as a docking protein that brought together ELF4 and LUX, but the latter two did not interact with each other without ELF3's help."

source: http://www.sciencedaily.com/releases/2011/07/110713161836.htm
 
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Thanks for you links chad, the first two links i could not tell if they where talking about photos or autos, but it seem like photos which makes alot of since. but you gotta think autos are different since they are mixed with RUDs, so it would be only right to assume that it doesn’t apply to them. but i could be wrong thats IMO but the last link is a science link and i really dont think the included the cannabis plant along with that study, its very good info and not saying any of it is wrong but cannabis is a different class of plant and autos are completely different from photos. Some thing apply to both photos and autos but then there’s some big differences and light is one of those sensitive things.
 
Thanks for you links chad, the first two links i could not tell if they where talking about photos or autos, but it seem like photos which makes alot of since. but you gotta think autos are different since they are mixed with RUDs, so it would be only right to assume that it doesn’t apply to them. but i could be wrong thats IMO but the last link is a science link and i really dont think the included the cannabis plant along with that study, its very good info and not saying any of it is wrong but cannabis is a different class of plant and autos are completely different from photos. Some thing apply to both photos and autos but then there’s some big differences and light is one of those sensitive things.

It stated (in the science link) that plants grow in the "spurts" (highly accelerated growth) just before the lights come back on (naturally, day).

If anybody, who has ever done a 24/0, and a 20/4 grow will tell you that there is noticeable growth during the 4 hour dark period.

But of-course, further studies need to be done in relation to light cycles for ruderalis.
 
"While most people assume that plants grow at a slow and steady rate throughout the day and night, Charles Darwin and others more than a century ago observed that they actually grow in spurts late at night, with plant stems elongating fastest in the hours just before dawn."

"More importantly, the biologists show how this protein complex is intricately coordinated through the biological clock with the genes that promote stem elongation in a way that could enable plant breeders to engineer new varieties of crops that grow faster, produce greater yields of food or generate more biomass per acre of land for conversion into biofuels."

"Because the three genes -- Early Flowering3 (or ELF3), ELF4 and LUX -- have biological activities that peak in the early evening, the UCSD biologists wondered if the three genes acted together in a protein complex. Through a series of experiments in yeast cells, they determined the three genes produced proteins that did interact with one another, but in a specific way. ELF3 served as a docking protein that brought together ELF4 and LUX, but the latter two did not interact with each other without ELF3's help."

Thanks. By 'night' and 'just before dawn', do you mean in terms of the actual time of day or in relation to the lighting schedule that one uses?
I was considering setting a 20/4 cycle but timing it so that the lights would actually be off during the warmest time of the day during winter (say 11am to 3pm) so that the heat loss would be kept to a minimum in the tent when the lights were off.
Right now, my plants are on a 20/4 cycle with the lights going off between 1am and 5am, which can be the coldest time of the day.
I don't know if plants can sense the actual time of day or if they just synch to whatever day/night schedule that you give them.
Maybe autos and photos are different in that sense as well.
It must be hard in winter to have the lights off for 12 hours and still keep the temps stable for photoperiod plants.
In any case, I do have a 700 watt oil radiator that would keep my tent warm enough if the temps became a problem.

Thanks to everyone for many helpful replies.

I really am eager to start the second grow but I think that my plants will need about one more month before I should harvest them.

This actually brings up another question:
Should you hang your plants to dry in the dark?
Could I hang them in the grow tent after harvest and still use the tent to start a new crop?
The tent would be the best place to keep them for me, but I really want to start a new crop as soon as I harvest the current plants.
The humidity gets down to 30% when the lights are on and the flap is closed, but as soon as I open the tent to water them or visit with them, I notice that the humidity quickly rises into the 40-50% range as the temps drop down into the low 20s C. I suspect that a closet in my house would probably have fairly high humidity and this might slow down the drying process.
 
Thanks. By 'night' and 'just before dawn', do you mean in terms of the actual time of day or in relation to the lighting schedule that one uses?
I was considering setting a 20/4 cycle but timing it so that the lights would actually be off during the warmest time of the day during winter (say 11am to 3pm) so that the heat loss would be kept to a minimum in the tent when the lights were off.
Right now, my plants are on a 20/4 cycle with the lights going off between 1am and 5am, which can be the coldest time of the day.
I don't know if plants can sense the actual time of day or if they just synch to whatever day/night schedule that you give them.
Maybe autos and photos are different in that sense as well.
It must be hard in winter to have the lights off for 12 hours and still keep the temps stable for photoperiod plants.
In any case, I do have a 700 watt oil radiator that would keep my tent warm enough if the temps became a problem.

Thanks to everyone for many helpful replies.

I really am eager to start the second grow but I think that my plants will need about one more month before I should harvest them.

This actually brings up another question:
Should you hang your plants to dry in the dark?
Could I hang them in the grow tent after harvest and still use the tent to start a new crop?
The tent would be the best place to keep them for me, but I really want to start a new crop as soon as I harvest the current plants.
The humidity gets down to 30% when the lights are on and the flap is closed, but as soon as I open the tent to water them or visit with them, I notice that the humidity quickly rises into the 40-50% range as the temps drop down into the low 20s C. I suspect that a closet in my house would probably have fairly high humidity and this might slow down the drying process.

To answer your first question, in relation to the light schedule.
Plants (to my knowledge) inside your tent have no possible way to sense the "real" time outside of the tent itself.

You should have your dark-period during the hottest part of the day, as too much heat can cause a slow-down in plant production (i think, if wrong, my apologies), so shutting off the lights would decrease heat (4 hour dark period).

Harvested bud should be hung in the dark with a fan and humidity levels should be kept at 50% (please double check). Light degrades THC, so you cannot have any lights on when you're drying. (you can dry in your grow tent, as long as the lights are off).

Here is an excellent Cutting,Trimming,Drying & Curing guide: After the Harvest - A Guide to Drying and Curing - Harvesting and Processing Medical Marijuana
 
It stated (in the science link) that plants grow in the "spurts" (highly accelerated growth) just before the lights come back on (naturally, day).

If anybody, who has ever done a 24/0, and a 20/4 grow will tell you that there is noticeable growth during the 4 hour dark period.

But of-course, further studies need to be done in relation to light cycles for ruderalis.

Without a link to a study I'm going to call malarkey on this. Basic botanical science states that plants grow during exposure to light, it's called photosynthesis 1 and 2. Big claims require big proof, and your claim is big.
 
plants need a dark period during the
vegetative cycle?
By Ed Rosenthal - Friday, October 24 2003
FOLLOW: ASK ED GROW TIPS, GROWING,
LIGHTS.
Does marijuana require a dark period during
the vegetative growth stage? I recently read
a grow book that advocated an 18-6 light
cycle during the early growth stages.
PSD 420,
Internet
One way in which plants are categorized is by
the way they gather and handle carbon
dioxide. Cannabis is a C3 plant. It uses the
CO2 it gathers during the light period, when
it is photosynthesizing. Plants designated C4
also gather CO2 during the dark period for
use during the light period. Many C3 plants,
including cannabis, do not need a rest
period. They continue to photosynthesize as
long as they are receiving light.
The plant's photosynthetic rate determines its
growth rate because the sugars are used by the
plant to build tissue and for energy. Cannabis
under continuous light will grow 33% faster than
the same plants on an 18-6 light regime.

Many C3 plants,
including cannabis, do not need a rest
period. They continue to photosynthesize as
long as they are receiving light.

Still not saying 24/0 is the best but...if you can keep your temps steady running that schedule than maybe it is the right method for you?

Whatever you decide...good luck and happy growing! :peace:
 
plants need a dark period during the
vegetative cycle?
By Ed Rosenthal - Friday, October 24 2003
FOLLOW: ASK ED GROW TIPS, GROWING,
LIGHTS.
Does marijuana require a dark period during
the vegetative growth stage? I recently read
a grow book that advocated an 18-6 light
cycle during the early growth stages.
PSD 420,
Internet
One way in which plants are categorized is by
the way they gather and handle carbon
dioxide. Cannabis is a C3 plant. It uses the
CO2 it gathers during the light period, when
it is photosynthesizing. Plants designated C4
also gather CO2 during the dark period for
use during the light period. Many C3 plants,
including cannabis, do not need a rest
period. They continue to photosynthesize as
long as they are receiving light.
The plant's photosynthetic rate determines its
growth rate because the sugars are used by the
plant to build tissue and for energy. Cannabis
under continuous light will grow 33% faster than
the same plants on an 18-6 light regime.



Still not saying 24/0 is the best but...if you can keep your temps steady running that schedule than maybe it is the right method for you?

Whatever you decide...good luck and happy growing! :peace:

even though im replying you saved me from having to

@ chad and everyone else , please read this and realise info along with sources you provide might be 100% correct for the plants you see for sale at wallmart but that same info can be completely false for a cannabis/C3 plant

a photo doesnt need darkness other then to turn on the flowering hormone button lol , and we are all aware autos dont need that darkness to kick the flowering hormones into gear

thanx pher you saved me a lot of typing/thinking

peace :Cool:
 
Wow is this thread smokin ?
I run 24/0 with my plants too, are they better than 20/4 or 18/6 ?
No idea, but are they ok ? Yes.
 
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