inside-aluminum foil on top of soil;outside-chicken wire on top of soil or motion sensor sprinkler heads. just teach them to get out of them & stay out. I have many house plants huge gardens and always have had cats. inside if you must you can spray with spray bottle then yell get out until they associate it all then you should be ok,it'll take awhile but they will learn you do not want them in your plants. eating them provide them with fresh grass or catnip.
Try Irish spring soap grate it up springcal it every where works for me.
I've had this same problem, after trying just about everything I finally found something that really worked: https://amzn.to/2VVRtAs
Spray ground areas with mix of clove oil, few drops dawn dish soap, essential oil of orange, tea tree oil, cayenne pepper and garlic. Mist above plants on an overcast day.
I've heard sprinkling cayenne pepper around the base of the plants works!