Planting/spreading vinca minor
I want to plant vinca minor between the sidewalk and the street, replacing the grass I killed last year. I'd like it to spread and fill in as quickly as possible. The dead turf is still there. When I plant the vinca, do I need to remove the turf down to bare soil, or can I dig small holes (4-5 in.) in the turf and expect it to spread OK? Also any idea how many small plants I'd need to fill in the space -- about 4 ft. deep by 80 ft. long. Any suggestions appreciated!