Starting with a 12/12 light cycle - a myth?

According to a small - but steadfast - group of growers, one can grow with a 12/12 light cycle for the duration of vegetative growth and flowering, and still end up with quality buds (only with a fairly small yield). Furthermore, these people claim that the incidence of female plants tends to be much greater, somewhere to the tune of 90% in fact.

Their reasoning is as follows: the plant won't begin flowering until it is structurally and chemically ready to, with both attributes being achieved by the presence of the light. Once ready, the plant jumps right into flowering and supposedly produces disirable flowers, only in a relatively small quantity.

The reality of the situation very likely isn't as rosy as these people make it out to be, but I'm still curious if anyone here has tried it and, if they have, what the results were.

Anybody?

 

I see that nobody has stepped up to answer this in the last few days - so I'll take a shot at it! I agree with the first point and disagree with the second.

Yes - plants can be forced into early flowering. As soon as they are able to flower - they will. Is it a good idea? That depends on what you think is important. If "lowest elapsed time" is important; then yeah, go for it. I believe that most people grow marijuana for the finished product (result) - not to push the envelope of what is possible (stunt). If you can shave two weeks off of a three month grow; that's what, about a 17% time saving. I'm just guessing, but I would say that same two weeks would cost you 50-70% in lost yield - much of the reduced yield is from only receiving 12/12 hours of light instead of 18/6 hours, as in a proper veg stage. So you are useing 1/3 less light hours and cutting the veg cycle in half. So the bottom line is - yeah, it'll work,but! I say give it the extra two weeks @ 18/6 hours of light and you'll be a happy farmer with a much better yield (50-70%)!!!

No - I don't believe a constant 12/12 hours of light will give you 90% females. As I recall, Nitrogen ratios, humidity and temperature have a known effect on female ratios. If a 12/12 light cycle will really give 90% females; I'm sure that's something we would all be interested in hearing about!

 

http://www.icmag.com/ic/showthread.php?t=51760

 

That link is exactly what I was looking for.

I might go ahead and give the 12/12 thing a try: I don't want my plants much taller than 30', I don't care that much about the yield since it's for personal use and I don't smoke a whole lot, and I really don't have much space that I want to devote to growing anyway.

I'll post results if I ever get this underway (which won't be for a few months at the earliest).

 

Thanks for the link Ham!

I'll have to look at it later, I'm out.

 

After reading Ham's link it makes a lot more sense. But it seems like they are still "vegging" under 12-12 light for about 3 weeks (+ or -) (untill they are mature enough to flower). It seems that the traditional veg time (and growth size it produces) is compensated by sprouting even more seeds per sq.ft. to get a good overall yield. This "12-12 From Seed" method has been around since the 80's, but I've never heard of it till now. Appearantly many old-timers have abandoned the idea. Everybody should read the link and decide for themselves. Remember, "If it sounds too good to be true - it probably is!".

Even if it does work as well as they claim (the very best growers can get 1 gram per watt per 11-12 week harvest); I didn't see anything about a 90% female ratio.
It's another way to grow that may, or may not, be better! On the plus side, you only need one grow light!

 

The supposed high female/male ratio was mentioned in another forum. It was basically just a few people agreeing with results of unusually high incidences of female plants, so there's a chance it was either a coincidence or total bullshit.

 

does anyone know when a seeds "chooses" its sex if it even does that, is it just by pure chance that mother selects when being sexed or does it make its own mind up and when does it do it

 

From what I can determine a seed is "predisposed" to be either male or female - that is to say that it has a tendancy to be one or the other. Under average conditions it will probably follow it's predisposition, a "female" seed will probably grow into a female plant or vice-versa.
This predisposition can be affected by the environment, giving a higher ratio than normal (50%-50%) of either females or males. In other words; you can manipulate the environment to get more females, just play with the temperature, humidity and the amount of Nitrogen in the nutrients! There's a good "Sticky" on how to do this, I think it's in the Techniques forum.