if miracle grow is used and mixed properly there is absolutly nothing wrong with. it you cant just go pick up a bag at the store and put it in a pot however unless its potting mix. yeah if you take miracle grow garden soil and put in straight in a pot you are gonna have shitty results. it needs perlite,peat ,and lime as the ph right out of the bag is absolutly 5.5 .and as for all the hating on synthetic macronutes, the people that talk smack about them are the same people that order a t-bone steak from beef that has been feed grain that is raised w/synthetic macronutes,or pours a nice tall glass of milk that came from a cow that has been fed hay that was raised w/synthetic macronutes there is absolutly nothing harmfull with synthetic nutes there all derived from the same place nitrogen,phosphorus,potassium,calcium,magnesium,and sulfur and all of those elements are of the earth with soil its personal prefrence not quantum mechanics