Raised garden beds

[phantom]

I'd like to raise the garden beds about 8 to 10 inches high around the perimeter of my property using a stone retaining wall. I want to protect the lower portion a cedar fence as I do not want the raised soil to come in contact with it at the rear of the bed. I've thought about adding a rear border made out of composite decking, fitting it around the posts and fence. Seems too labor intensive.

Any other ideas?