If your cat was an outdoor cat, she would naturally use the dirt to urinate of defecate. If she is urinating in your plants, it’s because dirt is her natural toilet.  I’m sure that you don’t want to remove all of the houseplants from your house but what can you do to stop this annoying behavior? The first thing that you should do is make sure that the cat’s litter box is clean.  A dirty litter box is not the cause of her behavior.  I know this will be a little extra work for you but you need to re pot your plants.  Once your cat has urinated in a plant, her smell is there and she is likely to go back to that plant again.  You’ll need to replace the soil and then you’ll need to put some kind of pet repellent on the plant. These repellents are sold in many pet and garden stores. You may also need a pet stain and odor remover if your cat “missed” and peed on the floor.