As we get older, it becomes more tiring to tend the plantings in ground level boxes, so we decided to elevate them to a more comfortable level.
These are 3x8 foot boxes, one foot deep.
I spaced the bottom planks to allow for drainage, covered the gaps with screen, and placed a one inch layer of gravel on the bottom.
Next came sifted dirt, with lots of organic material in it.
I then added soil amendment to the top, followed by a one inch topping of the sifted soil.