The miracle grow soil could be causing the leaf problems, did you have the yellowing before the transplant and were they in the same stuff? He means when the amount of sunlight starts to get shorter as the season progresses, MJ knows it's time to start flowering by the amount of light it recieves in a day (most types). I can't really say when it will begin as I don't do outdoor and it varies some across the country. The temp and humidity are Ok now, it's gonna get hot though, they'll survive. As far as watering goes, don't just water it all the time, over-watering can be a problem as much as no watering, feel the dirt, stick yer finger in there and when it's pretty dry, give it some, that could be where the yellowing is coming from also. I don't know a lot about the miracle soil but I have not heard good things about it, for MJ.