If you have trouble with rats and rodents it can be a nightmare trying to get rid of them. They are hardy and resilient, determined to find food or shelter in your garage or garden. Here are a few rat repellent plants you could use to keep them away.
Mint is often mentioned as a rat repellent. Many sites on the internet describe it used in various ways to deter rodents, particularly from houses. A high-potency oil can be mixed with water and sprayed onto areas where rats are causing a problem. The idea is that they don't like the smell and keep away. Considering that rats are renowned for living in sewers and eating from dustbins it seems unlikely that this will deter them for long. Another option is to soak cotton wool balls in the oil and leave them in entry and exit points.
Apparently Valerian attracts rats so if you happen to have a lot of Valerian plants and a rat problem it is probably worth digging them up.
Garlic has a strong sulphurous smell which rodents and many other pests do not like. Garlic cloves can be mixed with boiling water and the water then placed into a spray bottle to spray around the house. They also do not like tomato plants. Daffodils will keep rats away in the spring and they don't like marigolds or lavender either. Sage, pepper, oregano and cayenne will also help to keep them at bay. Herbs can be sprinkled on soil or around entry points. The strong smell might help to keep them away.