I just bought a new house and planned to put daffodils and vinca in the planting area just in front of the foundation. I discovered that the previous owners had put down a layer of white gravel (which I'm not fond of) to help prevent weeds. Several layers apparently. It goes down at least 6-8 inches, with some soil mixed in, maybe 40% soil at best in some areas, less in others. What should I do? Dig it all out and put in soil? Dig out some of it and mix with topsoil? Just leave it and try to plant the dafs and vinca anyway? Any other suggestions?