as far as I know there aren't any nutes in mg products.......that is why my poor little plants struggled earlier this year....i thought there were...then looked it up on the website...and there was none....so sad.
If you look in a bag of MiracleGro, there are little white balls that are made out of some kind of plastic. These balls are full of MG fert, the same kind they sell as a liquid in stores. When you water, some of the balls pop and let out a big dose of MG into the pot. The plants do like the MG, but they can be severely burned.
I used what is pretty much Miracle Gro on my grow, and it came out fine. Specifically, I used Smith and Hawken premium potting mix. I later found out that Scotts (the company that owns Miracle Gro) owns Smith and Hawken. I almost freaked out when I saw all the little white balls. I thought they were bug eggs at first. The trouble came in veg, when I was feeding my plants with FoxFarm Grow Big. I was giving them 1/2 strength, and then on my third dose (feeding every other watering) WHAM! I burned them all within an inch of their lives. The only explanation I can come up with is that the bubbles started popping, and the Miracle Gro made me accidentally overnute.
So, I suppose you can use Miracle Gro. But try to do your last transplant quite a while before flower. Otherwise, you will keep bringing in little nute balls, and never will know when they are going to pop.
S-Town
P.S. Fletch, your plants look great. I remembered that you used MG on your soil grow; and almost mentioned you in my first post here as a success story. You have a lot of experience, though. All of this advice is for newbies.