Most animals, including mouse predators, excrete ammonia in their urine, so when a mouse detects this odor, it usually goes the other way. One way to keep mice out of your kitchen, then, is to deploy a number of uncovered containers of household ammonia in places where you have seen evidence of mice. According to the Internet Center for Wildlife Damage Management, however, this repellant strategy will probably provide only temporary relief. Once hungry mice learn than no actual predators are around, they'll come back. Besides this, there's another problem. Mice themselves excrete ammonia in their urine, so they might not mind the smell at all.
A Simple Strategy
There's no need to spray ammonia or use it to wipe down surfaces. It just evaporates if you do that, and the smell won't hang around. The best way to maintain the ammonia odor in the area you're trying to protect is to put out small containers filled with liquid ammonia. Household ammonia – the kind you use for cleaning – is fine for this. Just fill a few bottle caps or small containers with the liquid, or soak cotton balls and put them near baseboards, under cabinets and tables and anywhere else you see mouse droppings or damage.
Do not put ammonia anywhere pets or children can reach it. Ammonia is poisonous. If someone in your house ingests ammonia, do not induce vomiting and seek immediate medical assistance.
Alternatives to Ammonia
The hazard involved with deploying uncovered containers of ammonia around your house coupled with its limited efficacy make ammonia a less-than-perfect choice for a mouse repellant. In fact, most repellents are ineffective, because mice tend to range over small areas, and the need for food and shelter usually overrides distaste for whichever repellant you use. However, if you want to use a natural or household repellant, some others that may be more effective than ammonia include:
- Peppermint oil
If you're serious about mouse control, you need to meticulously and regularly clean floors, countertops, cabinets and other places where you see evidence of mice. You also need to seal baseboards, floorboards and walls so that mice can't get in. Some other more-or-less humane mouse control tactics include getting a cat and trapping mice in live traps. If you catch a mouse in a live trap, relocate it at least a mile from your house – preferably in a field or forested area so it won't bother your neighbors.