pretty good vid almost two hours long, on growing. He says that using soil mix that is without fert is best because the grower can add fert later and it "removes the guesswork," but I disagree. You want the fert in the soil so you don't have to add anything. If you know for sure that your plant is showing a deficiency, find out what is needed and at it at that time. Otherwise fert in the soil is best. The rest of the video is pretty good.