I use Miracle Grow which is a 24-8-16 mix. Works for me. For flowering I use Jack's Classic Blossom Booster with a 10-30-20 mix. I start the 'girls' (clones) on a mild mixture of MG right after they take root and show signs of new leaves. Here's a shot of three of them about a month after cloning - they are about 14" high - should be ready for flowering in another month or so. I'll take clones from these in about two weeks.