Not that simple. They are autos. You have to start them in a big enough pot to begin with because autos should not be transplanted. At least that's the conventional advice. You can grow Cannabis in compost if you mix in plenty of limestone. Compost has a low PH and will lock out Phosphorus. That's what the red stems signify. I'm wondering about that "no up-potting" thing. Could be a myth. Has anyone here done it, or grown autos in hydro? I'd like to be able to to do a side by side hydro grow with a non auto and take a time lapse video of root development. Might do that at some future time. Right now, my dance card is full; A friend gifted me some Charlotte's web and Harlequin seeds. I'll be a few months sorting them out. So, any volunteers for the auto-flower investigation?