Half a centimetre is enough for most seeds, deep enough for the soil to grip the shell as the seedling pushes up. Buried too deep it exhausts stored energy before reaching light, too shallow and it emerges wearing the casing. Germination instructions on https://turboautoflowerseeds.com (https://turboautoflowerseeds.com) keep depth simple and consistent. Pointed end downward helps slightly, though seeds sort themselves out either way.