I heard from a top notch grower that if you start a seedling out on 12 hrs of light that there is a 80% chance it will be a female........? If you want a male(80% chance) you start out 18 hrs of light....


Now when I heard this it shocked the hell outta me. This was a guy off of Advanced Nutes web site.

yours truly
prop

Was it somebody from Adv. Nut. or just somebody cruzin their forum?

Tex

It was a movie, I dont know hes association
but you can check it out bellow.


https://americanmarijuana.org/CD/CD1/

Look towards the bottom right, the one with a cup of water, click that icon.

[wisc2]

I watched the clip. I was under the impression that sex was pre determined. Id like to hear a pro such as REZ or BOG give an opinion. If what he was saying was true why havent I heard of this before?

[TheIO]

i was under the impression that the sex was determined when the first set of real leaves are created....

Thats what I said, why havent I heard this before, surely someone has tried it here or on OverGrow.

Sex is not genetically predisposed, sex is determined by enviroment.

[Stewie]

I believe sex is pre deterimend, otherwise we wouldnt be able to create feminized seeds. Doesnt mean they cant change sex due to circumstances, nature adjusts to it's setting.
If a plants misses certain conditions, it can turn into a hermophrodite to make sure it keeps living on.
So i'd also believe putting em 12 hours to start, the way they didnt get grow in the original natural area's where they came from, (with some exceptions, there always are.... lowryder for one) it'll give bad results.
So, for some it might be a good idea. For the most, i dont think so. :/
Wonder what the rest has to say?

[GMT]

I have heard that restricting the root growth can improve the chances of creating a male plant when trying to create seeds. A nice deep (6 inch) space for roots to develop in to start with helps females to flourish. It only takes one male to pollinate many females so nature takes that into account when determining the ratio of male to females. A natural 80:20 ratio would be more than sufficient to maintain the species. And if you were a weed god, would you design the ones with room for roots or restricted room to be the females.

But like I said, I'm no expert.

[highlife4me]

Since everyone here seems a little confused I will say with confidence, sex IS predetermined; however, almost every seed has the potential to herm given enough stress, almost. And although we can't tell if a seed is male or female before growing it out, it is already destined to be male or female.

[mybeans420]

tests have shown that sex can be influenced by enviormental conditions. the reason you can create feminised seeds is that when you take pollen from a female plant that that pollen contains only female chromosones.

however, when seeds contain both chromosones they have the potential of going either way. enviomental factors act on triggers within the plants dna which will determine that seedlings sex within the first week or so. one thing that comes to mind is a good supply of nitrogen. (not overdone!!! worm castings in your starter mix can provide enough) is believed to increase the potential for females.

there are several other factors, but rather than try to remember them offhand i'll get back to you guys once i've dug the info back up and have had time to go back over it.
sit tight

peace,
beans