yeah bro or oats is the other term for it just sprinkle a cup of it around the base of the plant maybe a cup when you mix your soil no need for anything else either helps make the buds rock solid without the use of potash
not far bro you sort of want 2 ft by 2 ft hole go 3 foot wide you only need to dig it big enough to get established once it gets going it will go through anything the feeder roots spread out drinking roots go down black soil will hold water longer or if you dont wanna go back and water use...
ground dude add 2 hand fulls blood and bone 1 handful dolomite lime about 40 nitrophoska pellets and a half a teaspoon rootblast if u got it. this mix will last 3 months during vege if you only need a month veg flush it before it buds no need to buy soil just feed the one thats there if you want...