Miracle-Grow potting soil is OK, as stated, add about 30% perlite ... I used the 'organic' MG version, because it seemed to have the least added fertilizers, of their varieties ... I'm not on the 'organic bus', by a long shot ... I am not convinced the plant can tell the difference between nitrogen obtained from minerals, or obtained from rotting materials ... nitrogen is nitrogen, it's an element ... (I think)