Usually when I prepare a new place outdoors I remove all of the existing soil and replace it with my own but that just depends on how much stuff you want to haul to your plot.
What I would do is dig a hole and get rid of all that came out of the hole.
Find a good soil mix from that thread and put that in the hole.
Myself, I like to dig the hole just big enough for at least a 5 gal. container (but you really need a little more) and about 6 in. deeper(for drainage).
If you use buckets make sure you drill plenty of drainage holes.
The containers for me help me water less
just my
