I saw someone had searched the question in the title so figured ide give an answer.
of the plant is a photoperiod plant technically speaking you can veg it forever.You can also have that plant live on infinitely in clone form. Only issue with that is after a while people have reported the mom plants end product wont be as good as if it was a seed freshly popped from seed , or off a newer mom.
luckily They have solved that problem with the wonderful world of tissue culture.
so the other end of this are autoflowers which live and die regardless of Light cycle.I have heard of people successfully cloning autoflowers so you never know!
If you have any other questions let me know!