I know that a piece of a dark bag can be secured to the end of a branch using twist ties. taken on and off so that the branch receives 12 hours of light and 12 hours of darkness. Ex. On at 6PM off at 6AM.
To induce flowering for early sexing

but where do the balls or calyx form? at the normal place at the base of the branch?

any response would be appreciated

Take a look here...

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so yes, with this kind of 1 branch induced pre-flowering. the preflower will appear at the base of that 1 branch?

They should be at the base of all of the branches..

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even if u only cover one of the branches?

Oh sorry, didn't even read that part - damn I'm stoned! Ugh yea, I have never done this, but it seems like the logical answer to me.

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so yeah if you only cover one of the branches will the preflowers only show on that branch?

Ok, maybe not. I think we need someone else to step in on this one. That would mean you would be tricking just part of the plant and not the other parts. I dunno man, just pre-flower the whole thing?

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there is a section on this in the GrowFaq, but taht section doesnt address where the preflowers show up if you only do one branch