When the boxes are filled with bark for the first time I add 10% sand or about 3/4", the box is 9.50" deep. I add lime, alfalfa pellets, chicken litter (3-2-3) and slow release (16-4-8). I have done this so long I measure nothing. I till to mix everything and start planting. After planting I top dress with everything I tilled in the box except I do not add any more lime. When I order bark I order 60 yards because of the shipping, it cost the same to ship 10 yards as 60 yards.
