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CAN YOU TELL THE SEX OF CANNABIS SEEDS?

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kbag
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CAN YOU TELL THE SEX OF CANNABIS SEEDS?

Post by kbag »

Simple answer to this question is no. If you think you can i want some of what you are smoking.
Breeders do not go to all that effort to make feminized seeds for nothing. Even then this not 100% reliable you still get the odd male or hermaphrodite plants if put under stress while growing.
While being able to determine the sex of a cannabis seed by looking at it is a myth, being able to sex your cannabis early is not.
Normally, you would wait until your cannabis plants are done with vegetative growth, and switch them over to flowering. You then watch like a hawk for any signs of sex, and move the males as soon as possible. This is risky, though, because if you leave it too long, you risk the chance of pollination – turning your bud into seeds. Unless you are getting into breeding yourself, this is something you probably want to avoid. Myself this is the way i do it when growing a regular seed with feminized seeds.
If i am growing just regs then i want to sex them early how do i do this?
Well there is several ways to do this, one of my favourite ways is to veg the plants for 2-3 weeks then flip them to 12/12 and wait for them show sex.
You will need a loupe and closely monitor them, Once you have determined sex you weed out the males and then reveg your plants for a couple of weeks, a little long winded but works a treat.
Another way is to use a black bag over a small section of the plant during the vegetative stage to force pre-flowering, before allowing it to revert back.
Place a light tight, black, breathable bag on a lower branch of each plant for 12 hours a day.
It works by stimulating pre-flowering in that part of the plant; and as soon as you begin to see its sex, you can stop placing the bag over it, letting it revert back into its vegetative growth.

Do not be scared to grow regular seeds as it will give more choice when picking your seeds. Also some growers claim that the weed is more potent from regs seeds (personally i am on the fence with that one) but you can get some cracking strains that only come in regular seeds.
With that in mind i will leave you with a couple pics of a male and female parts.

Male plant


Female and male comparison

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Minty (Sat Aug 22, 2020 7:53 pm) • Sage (Sat Aug 22, 2020 9:31 pm)

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Re: CAN YOU TELL THE SEX OF CANNABIS SEEDS?

Post by Bulls »

Great write up kbag. Never knew the black bag over branch method.
Isn't it another way if you leave you plants in very small pots for longer than usual and they start showing sex too?

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Re: CAN YOU TELL THE SEX OF CANNABIS SEEDS?

Post by kbag »

Bulls wrote:
Sun Sep 02, 2018 5:52 am
Great write up kbag. Never knew the black bag over branch method.
Isn't it another way if you leave you plants in very small pots for longer than usual and they start showing sex too?
Interesting bulls it is not a method i have used or heard of tbh. Some plants you can basically see they are going to be male through veg or you know it will be one to keep a eye on. I guess this comes with experience and the only way to gain that experience is to grow regular seeds.Normally you can weed out the males long before they have chance to pollinate the females.

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Re: CAN YOU TELL THE SEX OF CANNABIS SEEDS?

Post by Nanook »

I've never heard of it either but I guess it could work. Good post :) might try it ( I only use clone of female seeds but it would show one way or other :) )
The quieter you become, the more you are able to hear.

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Re: CAN YOU TELL THE SEX OF CANNABIS SEEDS?

Post by Donks »

That's a great write up Kbag. Nice work :D

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Re: CAN YOU TELL THE SEX OF CANNABIS SEEDS?

Post by GMO »

Very nice info bite here dude

Thanks very much

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“If you can't explain it to a six year old, you don't understand it yourself.” -Albert Einstein

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Re: CAN YOU TELL THE SEX OF CANNABIS SEEDS?

Post by ohlordyeah_420 »

Awesome write up mate. I'm sure there'll be a regular strain I 'need' to try one day.
Although some of the breeders who do reg seeds are just starting to do fems (brothers grimm just released their cinderella 99 as a fem and it sold Out!)
diary link me do

"I fucking hate harvesting. I like planting the things and watering them, and looking after them, talking to them. I don't like fucking harvesting."

"You like smoking them, though."

"Oh, I like smoking them."
🏴󠁧󠁢󠁷󠁬󠁳󠁿

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Re: CAN YOU TELL THE SEX OF CANNABIS SEEDS?

Post by Hobbit »

Nice write up Kbag. Another way is that when the plants show maturity those two hairs at each axis tend to cross over each other in females but not males. Males tend to show sex earlier anyway. Having them in small pots definitely wont send em to flower they need the dark period to produce flowering hormones pot size is irrelevant. That bag trick mate have you tried it out, in my mind it doesnt make sense. I find it hard to imagine that once the plant starts producing flowering hormones that they would be confined to one part of the plant or the other way round ie the plant is mostly producing veg hormones and these stay localised to one part of the plant. Does make me wonder though as using CS method ive heard that you can just send one branch produce fem pollen. Also wonder what you could use that breathes and keeps the light out. Chin scratcher for me, id like to see it done if your keen to demonstrate it would be cool. Bloody cool post anyways, like a post that makes ya think.
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Re: CAN YOU TELL THE SEX OF CANNABIS SEEDS?

Post by kbag »

Yes i have used the black bag method once or twice in the past. Tbh though it is a pain in the arse removing and replacing every 12 hours. I was going to pop some 9lb hammer regs and document the method on here. Unfortunately my work would not allow this as i can be away from 12-15 hours a day. If things change in the future i will do it. As with the CS i have read that they treat one stem to get it hermaphrodite to pollinate itself. I am not a breeder but from what i have read they use cs to hermaphrodite one female of the same breed to pollinate a another female, to get feminized seeds.
One thing to note is most cannabis plants will show pre-flowers around week 6 some a littler earlier others later. So in essence the plant will show its sex still in the vegetative phase.

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Re: CAN YOU TELL THE SEX OF CANNABIS SEEDS?

Post by Hobbit »

Your bang on they should be showing sex earlier than e want to flower them, although I did find growing plots outdoors that if we removed ll maless some of the fems would then turn male, so we stripped the males, snapped em over rather than ripping them out and that seemed to stop that drama. I believe the CS method could be used both the ways you suggest.

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