18/6 vs 24/0

[SOG420]

I was wondering if anyone knew what would happen if Swim switched to 24/0 after having some plants at 18/ for 5 weeks.
Would this encourage new growth from younger plants but not affect older 5 week plants negatively. This is purely hypothetical I just wondered>

[hybridlove420]

"swim"....i thougt only the psychedelic forums used that term?

either way, swim turns his lights to 18/6 primarily for the purpose of saving 6hrs of energy per day. no idea if its better or worse for the plants than 24/7 tho.

best of luck to swiy

[GaGrown]

It has way less affect on the plants in veg than in flowering.. When flowering,the light cycle should should not be tampered with. Hermies!

[texas grass]

personal preference
power consumption

i like 18/6 cause it uses less power and its more natural for the plants

[daihashi]

personal preference
power consumption

i like 18/6 cause it uses less power and its more natural for the plants

Throughout my research of the stomata to try to figure out how we could manipulate it for our own benefit I found something interesting.

The plant will set it's clock based on the number of hours it receives light/dark.

Now what was interesting was this.. Was that even if the plant is in an enviorment that has lighting 24/7 the plant would develop it's own clock and actually go to sleep on it's own. This was indicated by stomata closure even during direct light after receiving light for 20 hours.

However for our purposes this is only useful to know for vegetative state as the 12/12 cycle is needed in flowering to promote certain hormones.

With that said... Use 18/6. Less electricity and the plant is going to rest on it's own even if you have your lights on 24 hours a day. :)

[fiddyonefiddy]

24/0 with blue spectrum for mother and clones
18/6 with red spectrum for veg
12/12 with red spectrum for flower
the plants love that blue spectrum and i may not even use the 18/6
anymore. seems like a waiste to me maybe im wrong.

[daihashi]

24/0 with blue spectrum for mother and clones
18/6 with red spectrum for veg
12/12 with red spectrum for flower
the plants love that blue spectrum and i may not even use the 18/6
anymore. seems like a waiste to me maybe im wrong.

Actually you still want blue spectrum for veg as well. Anything 5500k and above is good.

I'm not sure what you mean by that you might not use the 18/6 anymore. What are you going to go to 12/12? The plants really like 16+ hours of daylight a day when in veg. 24 hour lighting is not worth it either as the plant will develop it's own rest period regardless if the lights are on and off.

You might as well save the electricity and turn the lights off for a few hours a day during veg.

[fiddyonefiddy]

well they seem to love the blue for veg. is what i am saying .which ive always been told blue for grow red for flower. im doing a ghetto experiment on the dog chewed plants.the plant under 18/6 150 hps , became stretchy,thick and didnt do any branching and made huge fan leaves. the plant that lives under 24 hour flo looks like a bush. everything is the same except the light.

[daihashi]

the stretch comes more from the red spectrum (so I've read. Blue creates bushier plants and red causes some stretch.), not the 24 hours of light.

They are probably just getting more rest with 6 hours of rest. I think in my reading typically the stomata would close by itself after 20 hours. I wish I could find the link to that article.

[fiddyonefiddy]

well bushy is what i am after , the blue lite made four colas when the other only made one so definately blue light and as far as time im not sure i think to catch optimum stomata light time you leave the light on 24.these were chewed up so no telling if any of this is correct ...lol

[jmd1109]

I plan on experimenting with the duration of "lights on" cycle during grow.

In my limited research I've done to date, I've come across this a few times:

There is no scientific proof that the plant benefits from anymore than 18hrs of light during the grow (Veg) cycle...

As mentioned above, I do plan on finding an experimental truth to this very question, "Does the plant benefit from more than 18hrs of light during grow period"...

Even we can be force fed - :D

Enjoy!

:rasta:

[Xelatoth]

I am a biology major currently taking a plant physiology course and I can tell you, at least according to my botanist professor, that plants will not benefit from the extra 6 hours of light in any meaningful way.

Their stomatic gas exchange occurs during the dark period and while they may induce this behavior during constant light anyhow, there is something they can NOT do in 24 hour light:

Their "dark" reactions!!!

A plant has 2 photosystems and both light and dark reactions!

The plant's electron transport chains will be active during light periods to "harvest" the light into chemical energy...

Now, this energy will be stored for use at night!

At night, the plant uses that stored energy for input into the Calivin Cycle!

The Calvin Cycle is the MOST IMPORTANT metabolic pathway in a plant and it finally can convert the chemical energy into useable sugars with the waste byproduct being O2.

Basically, 18/6 is really the only choice

*** 24/0 will allow for a forced Calvin Cycle, but the plant will need to expend MORE ATP and NAD+ to get the same singular glucose molecule... more work for same result = less vigor!

Fo' real.. let us put this to rest as Mother Nature is the best scientist there is!

Peace

:smokin:

[the image reaper]

I am a biology major currently taking a plant physiology course and I can tell you, at least according to my botanist professor, that plants will not benefit from the extra 6 hours of light in any meaningful way.

Their stomatic gas exchange occurs during the dark period and while they may induce this behavior during constant light anyhow, there is something they can NOT do in 24 hour light:

Their "dark" reactions!!!

A plant has 2 photosystems and both light and dark reactions!

The plant's electron transport chains will be active during light periods to "harvest" the light into chemical energy...

Now, this energy will be stored for use at night!

At night, the plant uses that stored energy for input into the Calivin Cycle!

The Calvin Cycle is the MOST IMPORTANT metabolic pathway in a plant and it finally can convert the chemical energy into useable sugars with the waste byproduct being O2.

Basically, 18/6 is really the only choice
24/0 will allow for a forced Calvin Cycle, but the plant will need to expend MORE ATP and NAD+ to get the same singular glucose molecule... more work for same result = less vigor!

Fo' real.. let us put this to rest as Mother Nature is the best scientist there is!

Peace

The plant's Calivin Cycle will be active during light periods, but its
this is an excellent, educated explanation :thumbsup: ... there will still be some growers that insist they get better results from a 24/0 cycle, but I've tried every conceivable cycle imaginable, and I have never seen any advantage over 18/6 ... as I say to growers that insist on 'experimenting' with everything, " your plants survive your efforts, because they are WEEDS, and they don't thrive BECAUSE of your 'ideas', but, IN SPITE of your 'ideas' " ... when in doubt, 'imitate nature' ... :D

[Mr. Clandestine]

I'm partial to the 18/6 schedule for two reasons: 1) As Image Reaper suggested, in nature, plants don't get 24 hours of sunlight. I've never had substandard results from imitating nature, and don't know anyone who has. 2) Your power bill will thank you for that extra 6 hours of downtime if you're running 1k of lights or more, several ventilation fans, humidifier/dehumidifier, etc.

One upside to keeping a 24 hour schedule is that you don't have to worry about fluctuating temperatures. With fluorescent setups, the 24/0 schedule for vegging plants, clones, and mothers seems a bit more feasible. But still not entirely necessary.

[orangecommunist]

I am a biology major currently taking a plant physiology course and I can tell you, at least according to my botanist professor, that plants will not benefit from the extra 6 hours of light in any meaningful way.

Their stomatic gas exchange occurs during the dark period and while they may induce this behavior during constant light anyhow, there is something they can NOT do in 24 hour light:

Their "dark" reactions!!!

A plant has 2 photosystems and both light and dark reactions!

The plant's electron transport chains will be active during light periods to "harvest" the light into chemical energy...

Now, this energy will be stored for use at night!

At night, the plant uses that stored energy for input into the Calivin Cycle!

The Calvin Cycle is the MOST IMPORTANT metabolic pathway in a plant and it finally can convert the chemical energy into useable sugars with the waste byproduct being O2.

Basically, 18/6 is really the only choice

*** 24/0 will allow for a forced Calvin Cycle, but the plant will need to expend MORE ATP and NAD+ to get the same singular glucose molecule... more work for same result = less vigor!

Fo' real.. let us put this to rest as Mother Nature is the best scientist there is!

Peace

:smokin:
I know this is a very old thread but i would just like to clarify for any future readers that the 'dark' reactions, that occur in the Calvin cycle, are NOT reactions that only happen in darkness. The term 'dark reactions' refers to the fact that they occur independent of light. That is to say that these reactions can continue day or night until the plants stored energy is depleted. This is a very common misconception and i hate how many text books refer to them as 'dark reactions' as this confusion often arises with many of my students.

However, with some hardy plants, that grow in arid environments, the opening of the stomata (pores in the leaf) that allows for the intake of CO2 occurs only during darkness. This is so that there will be as little water loss as possible. I am not sure if this is the case for the marijuana plant but it would seem that knowing some of the evironments that it naturally occurs in and having read of its strong drought tolerence i would guess this may be the case. So though the above comment may have been technically innacurate in its information the practical application for what was said still remains solid.

18/6 may infact allow for faster growth as regardless of how much energy a plant has stored it cannot convert this energy to plant material without sufficient CO2 which it collects and stores during the cooler hours of the evening. But as always strain, genetics and individual environment will determine what is best for a plant. There are no universal rules as to what is best for marijuana plants.

[Dutch Pimp]

Hi OC...we kick this puppy about every six months...we don't get anywhere with it.

grower's choice

[oldmac]

..."Amen"


.:D.

[wraithe]

I found this to be good reading, I also noticed someone mentioned the Marijuana Horticuture-Indoor-Outdoor Medical Growers Bible. I have the electronic version if anyone needs it its about 140megs and I can post it on a anonymous site like rapidshare or something, if anyone is in need. Thanks for all the work put into this thread

[M.B.A.]

oldy but goody thread aye ;)

[daihashi]

My vote is still the same.

24/0 is a waste; plants create their own photocycle if forced into 24/7 light anyway and will rest on their own. Save the electricity and put extra cash in your pocket.

18/6 is where it's at

[M.B.A.]

My vote is still the same.

24/0 is a waste; plants create their own photocycle if forced into 24/7 light anyway and will rest on their own. Save the electricity and put extra cash in your pocket.

18/6 is where it's at

i concur

[Italiano715]

Another good thread on the same subject :D

which is better? 24/0 or 18/6 lights (http://boards.cannabis.com/indoor-growing/170311-better-24-0-18-6-lights.html)

[oldmac]

I found this to be good reading, I also noticed someone mentioned the Marijuana Horticuture-Indoor-Outdoor Medical Growers Bible. I have the electronic version if anyone needs it its about 140megs and I can post it on a anonymous site like rapidshare or something, if anyone is in need. Thanks for all the work put into this thread

Hey wraithe,

Saw you post this the other day, was busy and did not have time to respond.

I'd love to get a copy that way if you could. Many times Cervantes gets mentioned or quoted and I wind up having to go to the big city near me to a Borders to look in the "bible", but I'm not impressed enough with him to buy his book. :) Plus I'm cheap.

I tend to lean on a textbook by George Acquaah, called Horticulture Principles & Practices. While not mj specfic it deals with plant biology, how plant's work and how we can exploit how plant's work. Plus I had to buy it for a couple of horticultural classes I took a few years back. Cost abt $100 but I have found that it was worth it, always provides accurate information.:D

[Italiano715]

Hey wraithe,

Saw you post this the other day, was busy and did not have time to respond.

I'd love to get a copy that way if you could. Many times Cervantes gets mentioned or quoted and I wind up having to go to the big city near me to a Borders to look in the "bible", but I'm not impressed enough with him to buy his book. :) Plus I'm cheap.

I tend to lean on a textbook by George Acquaah, called Horticulture Principles & Practices. While not mj specfic it deals with plant biology, how plant's work and how we can exploit how plant's work. Plus I had to buy it for a couple of horticultural classes I took a few years back. Cost abt $100 but I have found that it was worth it, always provides accurate information.:D

Also, I forgot to mention in the rep.
On hand I have:

Biology Of Marijuana. From Gene To Behavior

Marijuana Botany. An Advanced Study. The Propagation And Breeding Of Distinctive Cannabis

The Science Of Marijuana

I can email you any book you may need just let me know! Also got the grow bible 4th edition and the same one mentioned above!

[overdose42024]

im interested in readin those books. can you send them to me??? [email protected]

[wraithe]

yea give em a day and ill host them on a free file hosting site just have to find one to accommodate 150megs

[wraithe]

ok try this link tell me if it works Marijuana_Horticuture_Indoor-Outdoor_Medical_Growers_Bible_2006.pdf - download now for free. File sharing. Software file sharing. Free file hosting. File upload. FileFactory.com (http://www.filefactory.com/file/a0a4d7a/n/Marijuana_Horticuture_Indoor-Outdoor_Medical_Growers_Bible_2006_pdf)

theres a 150meg/hour i dont know if thats per user or per link i just stumbled upon this service today

[oldmac]

ok try this link tell me if it works Marijuana_Horticuture_Indoor-Outdoor_Medical_Growers_Bible_2006.pdf - download now for free. File sharing. Software file sharing. Free file hosting. File upload. FileFactory.com (http://www.filefactory.com/file/a0a4d7a/n/Marijuana_Horticuture_Indoor-Outdoor_Medical_Growers_Bible_2006_pdf)

theres a 150meg/hour i dont know if thats per user or per link i just stumbled upon this service today

Thanks wraithe! I just downloaded it, so it's a working link.:thumbsup:

Download only took abt 6+ minutes, looks intact, I'll start to puruse it later today when I get more time.:)

[oldmac]

Also, I forgot to mention in the rep.
On hand I have:

Biology Of Marijuana. From Gene To Behavior

Marijuana Botany. An Advanced Study. The Propagation And Breeding Of Distinctive Cannabis

The Science Of Marijuana

I can email you any book you may need just let me know! Also got the grow bible 4th edition and the same one mentioned above!

Thanks Italiano,

I have the MJ Botany. An Advanced study..... I believe that's by Robert C. Clarke. I might be interested in the other two, but I'll let you know. I need to see what my granddaughter retrieved from my old computer recently. I had a metric ton of science papers and books stuck in my old broken computer for the last couple of years. I just got this AM an e-mail from her saying she had some success with the broken hard drive, she's going to see me next weekend.

[wraithe]

glad to hear it. if theres any other books your looking for lemme know I have a good line on digital books. And as always if you find the book helpful support the Author, if not then it wasnt worth it lol.

[Italiano715]

Thanks Italiano,

I have the MJ Botany. An Advanced study..... I believe that's by Robert C. Clarke. I might be interested in the other two, but I'll let you know. I need to see what my granddaughter retrieved from my old computer recently. I had a metric ton of science papers and books stuck in my old broken computer for the last couple of years. I just got this AM an e-mail from her saying she had some success with the broken hard drive, she's going to see me next weekend.


Your welcome. I have a plethora of cannabis related books. I have a hugeeee list, probably around 70 of them.

From: 123_Marijuana and cannabinoid research

To: Why End Prohibition?

It really is a goldmine! LOL


glad to hear it. if theres any other books your looking for lemme know I have a good line on digital books. And as always if you find the book helpful support the Author, if not then it wasnt worth it lol.

ditto ^^^^