The cats aren't scratching my couch or urinating on our carpet.
If your cat is urinating against a wall and is male, he is likely marking his territory. Scrubbing the area with citrus cleaner and placing some oranges nearby may work as a deterrent. However, un-neutered male cats have a stronger instinct to mark territory than other cats. Citrus may either not be a strong deterrent or may simply trigger a move to a different location for marking.
Cats tend to dislike the smell of citrus. A number of commercial cat training sprays contain citrus. However, a commercial citrus cleaner or a commercial citronella spray may have the same deterrent effect. If your cat is urinating in a potted plant, consider placing citrus peel in the plant as a deterrent. In some cases, simply rubbing an area with orange peel, ensuring you break the surface of the skin to facilitate citrus oil transfer, can work.
Deterrents should remain in place for at least a month after Kitty has been using the litter box regularly. When the treated areas are dry, a very affected product sold be Pioneer pet is “™”. You can also try a vinyl carpet runner to be placed (spike side up!) in the problem area. Small motion detectors are also very effective at keeping cats out of selected locations. Radio Shack sells a mini-motion detector that works well with cats. Don’t be tempted to protect the area by covering it with plastic as many cats particularly enjoy urinating on plastic.I too have been having problems with my cat urinating on my carpet for months now. I believe it has something to do with her age and inability to reach the litter box in time. While I completely sympathize with everyone that has been posting I wanted to let you know of a product that can help clean/get rid of the urine smell until you find a solution. By chance I came across a product called Scoe10x that claims to eliminate most any foul odor (including cat urine) and decided to give it a try. It is 100% safe to use around/on animals and humans and works like a charm! Each time I find a spot where my cat has urinated I try to soak it up if still wet, then apply a generous amount of the product. It takes at least 20 minutes of the spot being soaked for the enzymes to dissolve the bacteria. After using it we cannot even tell that there was a urine stain in that area. Works for lots of other odors as well. Good luck to everyone (including myself) on finding a deterrent. Cat urine is truly one of the WORST odors and hardest to get rid of!