Thing is if your worried they will get too big, don't over feed them and give them less light.
that way they will mature in age but not be too big.
I had one start under a 14 watt LED panel during winter, I topped it and did LST on her.
she grew slow and strong. over 8 weeks(plus) to mature . she was about 18 inches tall and 18 wide. a sweet little mother. now if I had her blazing under some power lights....yeah she would get big.
A mature plant when you start flowering will be way better than one thats younger.
If you start em young,yes you'll get a good harvest, but not her best.
You want to see pre flowers, and that takes about 8 weeks.