Things You'll Need
- Garden hose
- Hydrogen peroxide
- Baking soda
- Liquid dish soap
- Cat repellent or hormone spray
Instructions
Walk the outdoor area to determine where the cat urine smell is strongest---there may be multiple areas. You might need to wait for a day when there isn't much wind. If you know that your cat is the culprit, smell near windows and doors because your cat may be urinating there to prevent other cats from trying to enter your home.
Douse the location with spray from your garden hose to dilute the urine chemicals. This is best done immediately after the urine is deposited but is also is worth doing after a delayed discovery. If the spot is in an area where drainage is slow, rinse in one small area at a time to allow the water to drain into the yard. Repeat the process so as not to form puddles of standing water.
Use an enzyme cleaner at the concentrations specified by the manufacturer. These cleaners break down the components in the urine that cause the smell to linger. Recipes for homemade cleaners are also available, such as the one detailed by Home Life Weekly (see Resources) that contains hydrogen peroxide, baking soda and dish detergent. This mixture can be used on the ground and walls but not on ornamental plants.
Wait a day and then thoroughly spray water on the areas where you applied the cleaner. If you received rain after the cleaner was applied, you may want to repeat the process.
Keep cats out of the treated areas until you are sure the smell is gone. This may require installing barriers or squirting cats with a bit of water when they are found investigating areas that you want to keep off limits. You can try using a cat hormone spray on surfaces that are not too porous; such products deter cats from spraying and urinating in the area.
Tour your outdoor area after one or two days and decide if the urine smell has completely gone. If it persists, apply the enzyme cleaner again and repeat the process until the odor is neutralized. On very porous surfaces, such as unsealed wood on decks, you may have to remove the section and replace it if it was very saturated with urine.