It's not too late to change my soil this grow. I believe the only factor that changes is I need to lower my pH for soilless. I think that bag of soil only cost $15, so I wouldn't sweat it if I tossed it.It's one less variable, that's why I use it. Happy Frog comes with some nutes in it, which will effect how your other nutes work. If you are looking to figure out a schedule, it's easier if the only nutes are the ones you add. Will you get better results? That's a roll of the dice and your ability to recognize what the plants need when they need it.