How does cannabis know to Flower?

[GianniAppleSeed]

Does anyone know for certain? I haven't found any definitive info on this... and my question is ...
only talking photo cannabis here...

I know they say 12/12 to flower.... but does the plant itself realize that the night period is longer than the day period? and if so doesn't 11 on/13 off make more sense? or at least slightly more dark than light?

I read somewhere that cannabis will flower at 14/10 ?

 

[ArtfulCodger]

There isn't a single answer for every genetic. A cultivar that evolved near the equator and another that evolved at 35° N latitude will have different appetites for light. Here's a paper that talks about it, and also looks at the effects on yield and cannabinoid production.

Moving Away from 12:12; the Effect of Different Photoperiods on Biomass Yield and Cannabinoids in Medicinal Cannabis - PMC

The standard practice to initiate flowering in medicinal cannabis involves reducing the photoperiod from a long-day period to an equal duration cycle of 12 h light (12L)/12 h dark (12D). This method reflects the short-day flowering dependence of ...

pmc.ncbi.nlm.nih.gov

 

[RealFarmer]

For photos once they get about 12 hours of darkness they will start to flower. In nature they flower when the days get shorter so we mimic that indoor. The shorter days let the plant know it will die soon so it starts to flower in hopes to reproduce before it dies

 

[HerbalEdu]

you want to look into the role of phytochrome for cannabis:

What Is Phytochrome In Cannabis?

If you’re asking, "What is phytochrome?," chances are high that you cultivate cannabis. Understanding phytochrome and how this biological receptor truly functions, allows the grower to delve into the technical world of plant science and also to discover how to use this knowledge to their...

hightimes.com

also want to look into how work the release of florigen hormone that induce flowering triggered by phytochrome.

Florigen, the flowering hormone | CANNA Gardening USA

Many plants are ‘short-day’ plants, meaning that the plant starts to bloom on

www.cannagardening.com

 

[LoveGrowingIt]

you want to look into the role of phytochrome for cannabis

It's amazing how many types of photoreceptors there are in these plants.