Every morning our 8 year old male cat scratches a piece of furniture (usually closest to where he's been sleeping). This is after he's been inside for the night and ready to go out. I have bought an upright scratching post and covered it in catnip but he does not seem to be interested in it. Is there any product I can use on our furnishings that would deter a cat from scratching it? I have tried covering up the sofa and chair corners with towels and blankets but don't want to live in a house full of covered furniture all the time. Let me know if there are any better solutions.