Light cycle cuts down Flowering Time?

[GreenLeaf420]

I was on a forum and reading an article that was stating that changing the light cycle you can cut back flowering time and increase Yields..

If this is true it would be fantastic. I've read up on the Alternating Light Pattern Theory. Which people are claiming to also receive better results then all light's on.

The article discussed a growers experiments with 18 hour light cycles, based on the theory that plants were most efficient at gathering light during only a portion of the 'day' cycle. I want to say that during veg, he used 14 on 6 off, and during flower he used 6 on 12 off.

The grower claimed a 3 week shorter harvest cycle, with a 30-40% increase in yield.

Something about this rang true to me, and I want to reread the article, anyone know what I'm talking about or where to find more info? I've tried google, and of course the respective search functions on each site I frequent, with no luck.

Has anyone else Heard of this article?

Thanks GL420:jointsmile::jointsmile::jointsmile:

GreenLeaf420 Reviewed by GreenLeaf420 on 06-26-2008. Light cycle cuts down Flowering Time? I was on a forum and reading an article that was stating that changing the light cycle you can cut back flowering time and increase Yields.. If this is true it would be fantastic. I've read up on the Alternating Light Pattern Theory. Which people are claiming to also receive better results then all light's on. The article discussed a growers experiments with 18 hour light cycles, based on the theory that plants were most efficient at gathering light during only a portion of the 'day' Rating: 5

[GreenLeaf420]

Has anoyone ever heard of such things???

If this is true it would cut down on flower time!!!

[stinkyattic]

It will shorten flower time but at the expense of yield per harvest and per plant.
Try CO2 enrichment instead.

[GreenLeaf420]

Stink I already am using CO2 but the whole theory of going on a 18 Hr day with 6 on 12 off that is crazy. The CO2 will increase the yield but I never heard of it speeding up the flowering cycle. You have seen it or done it the hole 18 Hr day theory? I find it to be fascinating if it cut's back on flower time...

Thanks for the info GL420:jointsmile::jointsmile::jointsmile:

[GreenDestiny]

It's basically manipulating the circadian rhythm... It's assumed that since Earth has 24-hour days, all plants and animals are entrained to it. But in my opinion, not every plant or animal is created equal... 24 hours is just the average norm. Some things might do best with longer or shorter days...

I found the article you were talking about:
http://www.rollitup.org/advanced-mar...day-night.html
The source it references, http://www.intelli-cycle.com/information.php , doesn't seem to work anymore but is still in Google's cache

Too bad it says it gives the same yield... but doing it in less time with less power is still pretty awesome...

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Growing with an 18 hour Day/Night Cycle

The Theory
The theory behind the 18 hour Day/Night cycle is that during a normal 24 hour light cycle plants will usually achieve high growth rates peaking at 100% capacity during the first 50 - 60% of the day. The growth rates will then diminish rapidly and the last 20 - 30% of the day achieves minimal growth. So by reducing the length of the day we are triggering an increased growth mode where the growth rates are at their peak for the majority of the day. This effectively achieves a very fast growth cycle with full yield potential.

NOTE: To achieve these incredible growth rates it is important to provide maximum light intensities and CO2 enriched conditions. The recommended lighting is 600W per square metre.


The Cycles
Vegetative Cycle - Lights ON 14 hours, Lights OFF 4 hours
Flowering Cycle - Lights ON 6 hours, Lights OFF 12 hours

The Benefits
The growth acheived during an 18 hour cycle can be the equivalent to that acheived during a 24 hour cycle. So by running 18 hour cycles the same growth and yield can be acheived in 75% of the time.

Reduced day lengths also mean reduced power consumption. Grow more and use less power. Who can argue with that?

For example, an average crop grown from seed using a 24 hour day/night cycle will have a 4 weeks grow cycle and an 8 weeks flower cycle. This equates to 28 days @ 18 hours a day and 56 days @ 12 hours a day = 1176 hours of light over 12 weeks.

An accellerated crop using an 18 hour day/night cycle will achieve the same yields using a 3 week grow cycle and a 6 week flower cycle. This equates to 21 days @ 14 hours a day and 42 days @ 6 hours a day = 546 hours of light over 9 weeks resulting in a 40% reduction in power consumption and a 25% reduction in crop time.

[GreenDestiny]

If you use that method's principles and apply it to the photoperiod manipulation that's in the Grow FAQ, How do I manipulate the photoperiod for larger yields?, then you'd be one crazy weed growin sucka.

I'm too tired to figure it out on my own right now to see if the numbers would work for modifying that photoperiod scheme into the 18hr cycle... If it can be done, then I hope someone tries it. If not, just try the 18hr cycle by itself.

[GreenLeaf420]

So I guess it cuts down on time but like STINK said it probably cuts down the yield.

20-30% of the end light is only absorbed but it is absorbed and that probably effects yields. Every other article I'm reading is related to a new timer they are selling.

Has anyone tried this?

[JewBilly]

There is a thread at Effects of different photoperiods on flowering. - International Cannagraphic Magazine Forums with an experienced grower, Blckbrd, using 24/7 and 7/12 photoperiods. He claims identical results with less power consumption and 25% lest time. "I really do it to just speed up the harvest time. I like genetics that take 70+ days to flower and the 7/12 cycle is about 24% less time ( over two weeks less ) of flowering time. The finished product is huge, dense, and true to the genetic expectation. I have not observed any detriment at all."

[MistaJ]

Has anyone on this board experimented with time periods such as these?

[low_rdr]

I'm starting my next vegged plant at 7/12 - Its a clone from a plant that was ready in 7 weeks (pineapple express) - This one has been vegged for 6 weeks and is 24" from base to tip (although LST'd) and currently has about 40 nodes.

It'll be a week before I put it into flower.