Ok so here is the deal. In the back of my yard there seems to be a super old compost spot.........its got a sand bottom, basically like a pit, floods with a few ft of water every spring, ne way they tell me thats were they put leaves and grass every year. I dug it up and down under it stinks like the darkest forest soil, its black and close to coffee grounds in texture. Should i bother with it, i mean do a soil test/ my plan is to fill my 5 gal grow bags half way then take em out to woods fill rest of way with wood soil? Good idea or bad? basically my amendments and my compost stuff, then half real world dirt? what do ya think?