Hi, thanks for the reply.
As you can see in the image, the potted part of the trees is about the same height as the height of the bed behind it.
There is some soil already in the bed but only about an inch or two and I wanted to bring it closer to the top of the stones.
As for other plants, i don't know, maybe an azalea or some sort of flowering bush. Should plants like that and fruit trees not be planted together?
So I plan to plant those two trees in the bed, in the soil already there, but what additional soil should I get to put on top to bring it closer to the top of the stones? As far as I know, there isn't anywhere around here to get native soil. I was mostly just looking towards nurseries or Lowe's to buy soil to fill the area.