Create green space at the garage entrance / parking space

Hello everyone,
we have newly built and had our driveway to the garage or the parking area, which we want to pave, excavated, gravelled, and compacted.
However, since we are planning a flower bed in the area of the entrance, the flower bed area must be cleared of gravel again so that I can fill it with soil. How deep do I need to remove the gravel so that the roots have enough space and the water can drain?
Thank you very much for the help!

Depends on what you want to plant. There are some that grow quite well even in compacted gravel. And others don't like it at all. Tends to me I would remove everything, it's probably only 30-40cm. You don't need to worry about infiltration, gravel infiltrates very well

Thank you for the reply. Yes, I was leaning towards that as well. However, it is no more than 40 cm of gravel. I would have also secured the edge with [Tiefbordsteinen] or concreted it in. We are not entirely sure yet, but rather a mix of ground cover plants and small bushes/trees.