Your first line of defense when keeping cats out of your garden is to make sure that you have your boundaries secure.
If a cat has made his way into your garden, it may be hard to get him out. Most people choose to use dogs, simply because dogs are known to dislike cats.
All cats are known to despise water as well.
Protecting your plants is a different story.
If you visit your local hardware or lawn store, you can find motion activated sprinklers. They work great in keeping cats out of your garden.
Sound devices that feature high frequencies are also a great way to scare off cats, although they aren’t annoying to humans.
You can also use commercial repellents as well.
If you have a garden, it can be very annoying if cats and other animals decide to make your garden their home.