New Grower Benefits of 24/0 ?

[Milky]

I found this posted on another site:

"This is a direct quote from Ed Rosenthal whom most of you know is a marijuana growing guru:

Marijuana plants photosynthesize as long as they receive light as well as water, air, nutrients and suitable temperature. Photosynthesis is the process in which plants use the energy from light (primarily in the blue and red spectrum's) to combine carbon dioxide (CO2) from the air and water (H2O) to make sugar while releasing oxygen to the air.

Plants use sugars continuously to fuel metabolic processes (living) as well as for tissue building. The plant combines nitrogen (N) with the sugar to make amino acids, the building blocks of proteins. They are the substance of plant tissue. When the light is off, the plant's metabolic processes, respiration and growth, continue.

The plant can photosynthesize continuously so it produces the most energy and growth when the light is on, continuously. Continuous light does not stress the plant, which reacts somewhat mechanistically to it.

Plants under an 18-6 light-dark regimen are producing sugar only three quarters of the time. They are thus growing at only 75% of their potential. Leaving the light on continuously will result in bigger plants, faster, which leads to higher yields."

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"The following information is straight from Greg Green's "The Cannabis Grow Bible"

Cannabis is a light demanding plant. Professional growers keep the light on their plants using the 24/0 photoperiod for this reason. Plants that grow under 24/0 flourish and do not need a quantity of darkness in order to rest and perform photosynthesis properly. Plants that are grown in optimal conditions under 24/0 light regime grow vigorusly and the benefits of a 24/0 photoperiod can be seen actively in the results. More nodes are formed, more branches are created, leaf numbers increase, the plant is growing at its finest.

Some growers opt to use 18/6 as their photoperiod. This is 18 hours of light, six hours of darkness light regime. Under these conditions the plant will grow quite naturally but not as vigorously as the 24/0 photoperiod.

The 18/6 photoperiod expels 3/4 the amount of light that a 24/0 photoperiod does. Although this does not mean that a plant produces 1/4 less leaves,branches and nodes under the 18/6 photoperiod, it certainly does show the correlation between light and cannabis growth. As we have said already, cannabis is a light demanding plant. There are no problems associated with 24/0 and although some have attributed cannabis sexual dysfunction (the hermaphrodite conditon) to 18/6 photoperiod these problems are actually the result of heat stress.

A 24/0 photoperiod requires that your grow room temperature be kept well monitored. The 18/6 option is cheaper to run. You use a quarter less electricity and this will have an impact on your electricity bill. Also the 18/6 photoperiod will generally extend the bulb's lifespan. During the 6 hours of darkness the grow room is allowed to cool down for this period but a well maintained good grow room setup should not require a cooling down period.

24/0 and 18/6 both share the same problem though. Once you start the photoperiod you should keep that way especially when the plants near maturity (the preflowering stage). An irregular photoperiod can cause more males than females to develop. It can also cause sexual dysfunction to appear. Whether you choose 24/0 or 18/6 as your vegetative photoperiod try to keep that photoperiod unitl your plants are mature enough to express their sex."

 

[evol]

good info but those quotes are referring to photeriods in a vegetative state. I still believe the phytochrome production benefits autoflowers during flowering so they do require a dark period.
may be running 24 hours of light through the vegetative cycle then switching to less hours for flowering would work with autos but I don't really think so because it could stress them from the switch of lighting schedule.

 

[faded187]

ive grown 4 photos all which have hermied in the end from light leaks because I have no tent. that being said my plants even get light on lights out and very few have ever been stressed and only 2 hermied out of 21 auto grows. every one has finished under 73 days except my haze which went 89. not tryin to argue with any one just tryin to point out that everyone has there own opinions and styles. I really do love hearing everyones opinions but honestly im at the point in my grows where I believe I got it nailed ( in my opinion) to the point where I would have to bump my head pretty hard to just up and change tactics. now that bein said I believe people should start tryin their own tactics and see what works for them rather than just take someones word for it and start talkin like there the master grower. sorry but it happens a lot..until you try it you cant knock it or praise it. peace

 

[Milky]

good info but those quotes are referring to photeriods in a vegetative state. I still believe the phytochrome production benefits autoflowers during flowering so they do require a dark period.
may be running 24 hours of light through the vegetative cycle then switching to less hours for flowering would work with autos but I don't really think so because it could stress them from the switch of lighting schedule.

There seems to be a specific gene that tells the autoflower when to commence flowering and that phytochrome does not govern over that so how do you mean they benefit from phytochrome production?

And going from 24/0 to 20/4 by decreasing 15mins every day or every other day (resulting in a transition of 16/32 days) should probably be fine as you´re making the days shorter simulating near end of season. Or do you mean go herm?

This is an interesting read from August 5th 2014: http://sensiseeds.com/en/blog/all-about-autoflowering-cannabis/

And this on circadian rythms from August 6th 2014: http://sensiseeds.com/en/blog/circadian-rhythms-cannabis/

 

[evol]

I have no real scientific evidence to back it up but I believe because autoflowers contain indica/sativa genetics and not just ruderalis that phytochrome may still be produced with darkness. That is why some people suggest switching autos to 12/12 to kick in flowering if they are stubborn.


On another note, take tomato plants for example they do not require a dark period to flower or fruit but still benefit from a dark cycle to help photosynthesis, when the energy from the sunlight is converted into sugars in darkness. I think its pretty obvious that plants do benefit from dark.

 

[Milky]

I have no real scientific evidence to back it up but I believe because autoflowers contain indica/sativa genetics and not just ruderalis that phytochrome may still be produced with darkness. That is why some people suggest switching autos to 12/12 to kick in flowering if they are stubborn.


On another note, take tomato plants for example they do not require a dark period to flower or fruit but still benefit from a dark cycle to help photosynthesis, when the energy from the sunlight is converted into sugars in darkness. I think its pretty obvious that plants do benefit from dark.

Well I haven't got a clue Evol but from everything I've read up to this point suggests that C3's still goes on ticking in the dark but at a lower rate compared to being bathed in light. And maybe it's a waste of energy stretching for light as that could go into stretching everything else on the plant "symmetrically"?

It would be nice if more research could be done on this subject. We need to know what else the phytochrome does besides measuring the photoperiod and trigger and manage flowering.

 

[Bilbo]

Now that summer is gone I'm going to keep a big CFL on 24hrs in the tent to provide heat.

I've decided to do this on the basis that I know it's too cold for the plant without adding heat but it's uncertain if it makes a difference giving them darkness and I can't be bothered wasting heater watts/plug sockets/tent space on an uncertainty