Perennial cannabis??

No, once it flowers, thats it. In equitorial tropical zones with little difference in day length and temps, Sativa plants may flower and re-flower for many months, giving the appearance of lasting for more than a season, but in reality they just can't distinguish between summer and winter and may live close to 18 months, but they still only have one vegetive cycle and one flowering cycle before dying. Hope this helps, Organoman.

No, unless it gets fertilized, and drops seeds.

Nope. She grows, flowers, and dies based on light cycles. There is a chance if you do not harvest and just let it die it will hermie and drop seeds, and new plants will try to grow next season.

Cannabis is an annual plant by nature. The only way we keep it alive so long is by exploiting the photoperiod aspect of it. If you where to leave it out, it will go into flower and die, It will not reveg unless supplemental lighting is added in. Add enough stress of not being pollinated, cold temps, end of season lighting and the plant will self pollinate itself then die. It can be kept in veg for an extra extended period of time but not flower. Good Luck!