I grow in rock wool cube's to start all the young seedling's or be it clone's,Once the seed has split i leave it till it has at least a tail about 5/8 mm then make a hole in what tever grow medium that you grow in drop the seed in.But make sure that the seed is no deeper than a couple of mm or it could grow back on its self takeing longer to germanate.I do it so that the tail is just below the surface the gentlely push the side in this takes a realy steady hand or the seed tail will be bust then i cover with a small piece of rock wool cube keep moist spray 2 times a day but dont go mad.If you are growing in soilmake a hole a little bigger than the seed drop the tail end in then fill with sioil that you have rubbed between your hands to take away any excess lumps.Then put straight under cfl's or flouresents i have even done it with h.p.s this can be a good way of makeing the plants more hardy to heat.Get the lights has close to the tops of the plants after 2 week give them a week to get used of the room then lower the light to 6/8 ince of the tops of the plants,This will give you tight internodes intern a bigger crop.