Do you still have a raw edge on your quilt? If so, it's common to finish it with a binding. You could use wide blanket binding, but it would be very difficult to sew on without a lot of rippling. Traditional quilt binding methods would be much easier.
Traditional quilt bindings do not have to be narrow, but they usually are. If you want a border around your quilt, you usually work that into your top design rather than adding it as a binding.
There are ways to add a ruffle, prairie points, etc. also.