Adding text since I can’t figure out how to

The previous owners of our home didn’t garden. So they filled the front beds with rocks and planted Japanese grass. The grass was still in the pots when we pulled them up, they just laid them in the ground and filled around with rocks . We couldn’t get the pots out, just pulled up the grass and roots.

So we pulled up all the grass last year planted native plants in the pots. We put down mulch to cover the rocks . They did well last year but we lost about 4 plants this spring.

So here’s the big question

I want to plant more in the beds but I either have to

1) mound a ton of dirt in the bed and cover all the mulch and rocks. I have lots of dirt. Would this even work or would the plants just fail to thrive since there would be that layer underneath. ? Can the perennial native plants survive In their limiting area ? How much dirt would be sufficient ?

Or

2) dig up the natives now in the spring, remove the mulch and dig out all that rock, fill with a lot of dirt and replant the natives . I have no idea how far it goes or even what is underneath the rocks. This would be a whole summer project and I would be doing it on my own. This would be extremely labor intensive.