Okay, i dont want to worry you or anything, but i just noticed on the miracle grow link, it reads; Feeds for up to 3-months its not a good idea to use this soil for a starter, my advice would be to keep the miracle grow for more mature plants, get some good compost, one that has no nutrients in it, and use it for your plants until they reach about 1.5ft tall, then re-pot them into the miracle grow soil, that way you know your plants arent taking up nutes too early, basically just dont put young plants in that soil, and i guess it may be hard to flush out all nutes towards the end of flowering if you use that soil, thats just my two cents, go and get some normal compost, without nutes.... your plants will love you for it...