Any reasons why I shouldn't start seedlings @ 12/12 from the getgo, in order to figure gender?

Hello there,

I'm late but I think it's important to explain something.


Genetic age or biological age (that's what it's called if I remember correctly):

-A plant from seed that has just germinated at 18/6 cycle has a genetic age of 1 day.
-A plant from seed that is at the 20th day of 18/6 have a genetic age of 20 days.
-A cut/clone from a 10-year-old mother plant maintain at 18/6 will have a genetic age of 10 years.



From seed, the time needed for the genetics to "stabilise" and become mature is 60 days of 18/6.
This is particularly necessary if you plan to do crosses/F2s or if you have a new mother plant from seed that you plan to take cuttings.

Theoretically, plants from seeds that are going to flowering before 60 days of growth will produce less powerful buds.

Personally, I lauch my plants into flowering after 40 days of 18/6, I think that's a sufficient genetic age to have a very strong product. But if you can go up to 60 days growth, that's even better.

This is only for production but if im going to make a cross or take cuttings for breeding I will always wait at least 60 days of 18/6 starting from seeds.

The only way to start directly whit flowering is to have cuts from a mother plant who have a genetic age of +60 days.

Source : Jorge Cervantes

(Sorry for my bad english).
 
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Zero0 said:
Hello there,

I'm late but I think it's important to explain something.


Genetic age or biological age (that's what it's called if I remember correctly):

-A plant from seed that has just germinated at 18/6 cycle has a genetic age of 1 day.
-A plant from seed that is at the 20th day of 18/6 have a genetic age of 20 days.
-A cut/clone from a 10-year-old mother plant maintain at 18/6 will have a genetic age of 10 years.



From seed, the time needed for the genetics to "stabilise" and become mature is 60 days of 18/6.
This is particularly necessary if you plan to do crosses/F2s or if you have a new mother plant from seed that you plan to take cuttings.

Theoretically, plants from seeds that are going to flowering before 60 days of growth will produce less powerful buds.

Personally, I lauch my plants into flowering after 40 days of 18/6, I think that's a sufficient genetic age to have a very strong product. But if you can go up to 60 days growth, that's even better.

This is only for production but if im going to make a cross or take cuttings for breeding I will always wait at least 60 days of 18/6 starting from seeds.

The only way to start directly whit flowering is to have cuts from a mother plant who have a genetic age of +60 days.

Source : Jorge Cervantes
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Hello, when quoting someone, it's helpful to use actual quotation marks to mark where the quote starts and ends. Hard to tell from your post what Cervantes actually said; and what he didn't; but if you're just "paraphrasing" him, then quotation marks aren't necessary.

At any rate, Shantibaba says MNS seeds can be flowered after as little as 2 or 3 weeks in veg, after the first set of true leaves. Some varieties (cultivars) start out slow in veg, and could use the extra week, or two before bloom; but most seasoned growers will veg from seed for at least 3 weeks, after the first set of true leaves appear.

I don't think a 60 day veg period produces more THC. The 18/6 veg light cycle is relative, or not a hard fast rule. If you're the curious type and like to experiment, for educational purposes, then give this veg light cycle a try: 12-5.5-1.0-5.5 ... so, that's 12 on, 5.5 off, 1 hr on, 5.5 off. Without 12 hrs of straight, unbroken darkness, they won't bloom; guaranteed. That's the veg cycle I'd use for a 60 day veg period, in a tent. If you try that, then the alternative bloom cycle would be 8 hrs on, 16 hrs off. That's 5 hrs less light. They'll bloom, no problem. That bloom cycle is especially suited to pure sativas and sativa dominant hybrids.

You don't need to use your main grow light for the 1 hour on period. A single 35-40 watt warm white grow light (3000k) in the middle of your tent is enough to keep them in veg. Just make sure the small night light isn't cool white, with more blue than red.
 
Freedom_Fighter said:
Without 12 hrs of straight, unbroken darkness, they won't bloom; guaranteed.
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The above statement is a generalization, of course, since some cultivars will bloom with only 6 hours of unbroken darkness, while others may require 10 - 13 hours. The point being to interrupt that lights-off period, whatever it be, with an hour of light in the middle of it, to prevent bloom. If a cultivar blooms under 6 hrs of darkness, then restricting the lights off to a max of 5.5 hrs will likely keep them in veg.
 
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I think playing whit the light cycle increase the probability of hermas.
I strictly run every strain whit 18/6 cycle for veg and 12/12 cycle for flowering until the end.
But that's only my opinion.

About the theory of Jorge Cervantes I think it's logical cuz most strains in nature have 2 or 3 months of veg period during summer.
Maybe some indicas have shorters periods.
 
Zero0 said:
I think playing whit the light cycle increase the probability of hermas.
I strictly run every strain whit 18/6 cycle for veg and 12/12 cycle for flowering until the end.
But that's only my opinion.
Click to expand...

Have you tested your theory? How many hermies did you get from the alternate light cycle test?

Zero0 said:
About the theory of Jorge Cervantes I think it's logical cuz most strains in nature have 2 or 3 months of veg period during summer.
Maybe some indicas have shorters periods.
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Yes, it does seem logical but take nothing for granted. Test all things (theories), whenever you can, to verify. Sometimes it's inconvenient if not impossible to be rigorous about it. In which case, follow your logic and let it evolve.

So, assuming a 60 day veg is full maturity, then it seems logical to veg a "designated" mother for at least 30 days before taking cuts; and the 30 day old cuts are vegged for another 30 days, making them 60 days old and ready to bloom.

Or maybe you prefer a 45 day veg for the mother, for stronger cuts, in which case you would only need to veg them for another 15 days, once rooted and transplanted; giving you your 60 days. All subsequent cuts from her, can come straight out of the gate at 12/12.
 
I never tested changing the light cycle.
Also cuz I prefer let sativas goes for long flowering.

Now I remember the other rule Jorge Cervantes say in his book, when your start from seed the earliest moment to start flowering is when your plant have at least 5 floors/nodes and this occure at ~40 days.
But he advise it's better to go for 60 veg days for breeding.

Well, I have make F2s of Dirt Dawg from Top Dawg seeds whit 40 days veg time years ago and the F2s are as strong as the F1s.
 
Freedom_Fighter said:
So, assuming a 60 day veg is full maturity, then it seems logical to veg a "designated" mother for at least 30 days before taking cuts; and the 30 day old cuts are vegged for another 30 days, making them 60 days old and ready to bloom.

Or maybe you prefer a 45 day veg for the mother, for stronger cuts, in which case you would only need to veg them for another 15 days, once rooted and transplanted; giving you your 60 days. All subsequent cuts from her, can come straight out of the gate at 12/12.
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I don't know if it works like that...but I think not.
 
Zero0 said:
I think playing whit the light cycle increase the probability of hermas.
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If that's true, which I doubt, it would only be true of hermie and feminized plants; but not true of a true female, according to Neville S. True females aren't that easily triggered into growing a pair of nuts; but if by chance it does, it is highly unlikely to be more than a single sterile male flower. Look into it. He put that theory to a rigorous test on one occasion, when he attempted to reverse an entire room of true females to get them all to produce balls. He claimed to spray every plant in the room with liberal amounts of the chemical He used, to force reversal, but after a very thorough inspection of all plants, only found 3 plants that presented a single male flower on each, all which failed to produce any viable pollen.
 
Some people think if you induce stress to your plants they can be stronger.

Other people, like Jorge Cervantes or me, think that the less a plant is stressed, the stronger it is.

But as plant cultivation depends also on empirical knowledge, it is difficult to make 100% accurate claims.
 
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politoed said:
you can also do a version of that but not as extreme. grow them on normal 18/6 and around week 3 or so, leave them in 24 hours of darkness. then go back to 18/6.. bro science says theyll shoot some flowering hormones, enough to show sex earlier, but not enough to actually start flowering.

id concur with some of the above posts to avoid the reveg. i have tried starting seedlings and later flipping them, the reveg really butchers the structure especially on some sativa girls. then you gotta reveg them a while to get them strong enough to support buds, and you actually lose more time that way. its faster to just be patient and wait.

id try the method i said in the first paragraph or even paying for a sex test if its that urgent.
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IMHO Revegging females is hard to accomplish-it' s time consuming and does not always work.I agree with those who go with a regular light cycle and let them show sex when ready and then cull any males you don't want.This way they will grow full bore with no interuption.Actually this is what Todd Mc Cormick reccomends at Authentic Genetics.
 
Take a cutting and put it into a glass of water with some clonex gel mixed into the water giving it a very light pink color. It will give some trace nutrients and u can put the glass of water and cutting on 12/12 and sex it that way. I have found trying to reveg males to be extremely frustrating and like others said, let your plant get big and strong on a normal light schedule.
 
Diesel840 said:
Take a cutting and put it into a glass of water with some clonex gel mixed into the water giving it a very light pink color. It will give some trace nutrients and u can put the glass of water and cutting on 12/12 and sex it that way. I have found trying to reveg males to be extremely frustrating and like others said, let your plant get big and strong on a normal light schedule.
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I like that cutting idea.Never thought of that.
 
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