You should always listen to your father, he knows best!!!! I agree father jack, I can tell you've been there , done that. Rich potting soil is too much for those tender little babes feet. I ALWAYS use Pro Mix with a tiny bit of DOLOMITE lime. You could use 5% potting soil in the mix but NO fertilizer will be needed til after transplant to big containers. Even then if you make the right soil mix you shouldn't need to fertilize at all . TOO MUCH LOVE CAN KILL YOUR PLANTS. love them less they'll love you more.