Normal Growth?

These White Widow plants were all started at the same time, the first four were no more than week apart. Out of the other six one just started and the others have some small roots but no leaves have come up yet and its been a little while. This is my first grow, going with aeroponics. I used filtered water and just started giving 30% nutes, in the morning till the sun is no longer in place I leave them outside in the sun then back under a small floro untill they are ready for HPS..when would that be?

Also I do take care outside not to expose to pests and they have reacted good to the outside light....I put them out win it hits 68 and out when it hits 90 or if the suns gone, the growth accelerated when I started doing this.