My basic understanding of when a plant is done vegging outdoors is that it is determined by when the sun in your area goes into a 12 hours light/12 hours dark cycle. There are charts available online for you to review to determine when your particular area will be in such zone/cycle - seems like you can search for daylight hours almanac or some other such key words.

Once your zone goes into a 12/12 cycle, then your plant will begin to show signs of sex, hopefully for you it will begin to flower (signs of female sex) - the flowering cycle.

With that said, if your plant does not receive sufficient direct sunlight, if your nutrients are not exactly in line, or if you have a strain of MJ that is autoflowering (such as Lowryder) a plant may/can begin to show signs of sex earlier, thereby producing seeds, if male, or begin flowering if female.

Basically, just sit back and watch your plant grow, and it will do its thing. Give it the basics of water and read within this board for some threads discussing nutrients. I've come to be a firm believer in keeping a grow simple, as a lot of grows result in plant death due to the interference of the grower.

I hope this has helped a bit. If not, then search the board, as I am certain you will find additional and more elaborate answers.

Good luck, my friend! Be good out there!