How can I keep my cat out of the flower beds?
From experience it is very difficult to deter a cat from exploring a garden once it has decided it’s the ideal place to do their digging, scratching, roaming and/or toilet.
Cats love freshly worked soil. What you need to do is create a barrier in the area being damaged. Short branches pushed into the soil as close together as possible can be a good deterrent. After digging or tilling an area try inserting pruned branches from your garden or just lay the branches on top of the soil. Sharp prickly branches will stop the animals from getting too comfortable in an area and hopefully they will move on. Sharp edged pine cones, egg shells and stones will also work.
It has been suggested that some plants give off smells that cats dislike. One such plant, Coleus canina, goes by the common name, “scaredy cat plant.” Other plants often recommended for keeping cats away from yards are rue, lavender and pennyroyal. You can plant these between your other plants. The smell of lemon/orange rind can also act as a deterrent so put that around your plants.
You mention that it is your own cat, so it might be a good idea to provide a cat-friendly area to attract it away from your flower beds.
Plant a separate bed of catnip plants, in another part of the garden. Hopefully your cat will come to view this part of the garden as their own, thereby leaving your flower beds alone. If you have a problem with the cat pooping then make a sandbox and keep it in close proximity to the catnip plants. You will have to clean up the cat poop afterward, but at least it will be contained.
Hopefully one or more of these ideas will work for you. Good luck.