The answer to 'natural rat repellent' is to use a combination of natural deterrents and exclusion methods to keep rats away from your home. Some effective natural rat repellents include peppermint oil, cayenne pepper, castor oil, and ammonia-soaked cotton balls. These scents and irritants can help drive rats away without the use of harsh chemicals.
To use these natural repellents effectively, apply them around entry points, under sinks, and in other areas where you've seen signs of rat activity. Reapply every 2-3 weeks, or after heavy rain or cleaning. Pair these repellents with sealing any cracks and holes in your home's exterior to eliminate access points for rats.