Pre-determining sex, the Genefinder method

How to pre-determine the gender of your plants
The Genefinder method

The following lines were taken from two different threads discussing pre-determining the sex of your plants started by Genefinder, I am placing some Q&A’s with related info as well so expect occasional editing.
The original text is already no longer online availlable so i am placing this here for future reference.

GWhizz @
When and how can I pre-determine the sex of my seedlings.
Genefinder @
High whizz, it's good to grow them until they are mature enough to flower, if you want to show sex early and still carry on vegging them, then you put them into flower for around 3 days depending on the maturation times of the strain) and then revert back to 18/6, this allows you to see a few preflowers without the plant going into flower or reducing the leaflet number, usually you can see sex 5 days after going back to 18/6. wait until they are around 4 weeks old or have three actively growing internodes before doing this, you then have the choice to use the seedlings as mothers without the risk of having males or just to give you more space for the remaining females. I have grown this strain for years and it's a big yielder, with large bracts and a sweet aniseed taste.hope this helps. peace Genefinder

Watt tyler @
Just a quick question about using the genefinder method:- when would be a good time to start it (how long in veg from seed/clone) and how long should you leave plants back in veg state after genefinder(after 3 days 12/12) before putting them into flower properly?
Smokey @
you can use it anytime on a decent sized plant, as long as its not a little seedling... roughly about 6 weeks from seed. And after you used the genefinder method, you can revert back to vegging and put the plants in flower whenever.
you basically switch the timer to 12/12 for a few days and then back to 20/4. this is a good way to tell sex. 2 out of my 3 plants showed pistils&balls 10+ days after i went 12/12.

Barnzo @
Does the genefinder method work without fail.
Putting plants onto 12/12 for three day then back to 18/6. Will this always show the sex about a week later?
Twisted Rizla @
Pretty much. Some will take longer though and there's nothing much you can do about that.

Barnzo @
and when you reveg the plants that the genefinder method has been used, you can still take cuttings from it later on? For mothers?
Muppet @
Don't see why not, but why not take a cuttin' now in case you really like it and it won't re-veg?

Barnzo @
and if i do use this method and i have say 3 males and 2 females and have already gone back to 18/6 will they still have a chance to pollinate the females?
Church @
You should remove the males as soon as possible - it's unlikely that they will pollinate your crops at this stage - the pollen pods need to form first... but you can never get a male out of the room too soon!
Also, the males will probably show first.

elvis loved burgers @
Jan 27 2008, 01:47 PM
If I wanted to tell the sex of the plants before they reched maturity, I know that I can take cuttings and force flower them to show the sex, but do I have to wait for the clones to root or if I just stick the fresh cutting underr 12/12 will they show sex?
Amsterdammer @
Yep, you can place the freshly cut clone in a glass of water and put them straight into flowering, they will stay allive like a fresh cut rose and WILL start to flower withing that strains normal flowering period.
My “clones” for sextesting stay alive for a good two three weeks without any problems.

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