Estimating age of a clone, when to put into flower

I rescued this clone from a friend's backyard in July. The only info I have is that it is Durban Poison. He got this clone on July 4th and it was 2 ft tall. It is now close to 4 ft tall. It has been pushing pistols since I got it. How do I know when it is time to put into flower?.

Another pic of it

Now ? Or whenever you're ready . Clones are generally taken from mature plants , so they are the same age as the mother .

I'm not a fan of bringing outside plants, inside.
Bugs mostly.

Good luck