Sinking garden bed question
I am new to gardening and I have noticed that some of my new garden beds have sunk somewhat in just the first year. The beds were a mixture of the existing moderately clay soil along with lots of store-bought triple mix. I guess it was initially reasonably fluffy and now it is fairly compacted down by rain and occasional foot traffic.
I can easily add more soil/compost to level out the bed, but my worry is the shrubs planted on top. They are sinking along with the soil, and so if I add more on top it would just start to bury the plants.
Is there anything I can do with my soil to help slow down this sinking? To get the shrubs back up is there anything I can do aside from having to re-plant them? It looks like they sank about an inch. The rest of my lawn is not sinking...just my garden beds.