if i was you i would keep one mother because you dont need more than one.
I would put 6 plants in the flower zone however i would veg them in there untill they were about half a meter tall then take the 4 strongest and transplant them into larger pots.
With your vertical heighth you want to get them as tall as possible, i would toss a 250 watt hps in there with some flouro's when they get taller.