Keeping cats out of flowerbeds has long been a problem for the home gardener. If the cats in the neighborhood, including your own , are scratching in your garden, turning it into their personal litter box, its time to take action. There is no single answer or simple solution to the problem. However there are many home remedies that people swear by.
If you know the cat’s owner, talk to your neighbor first and explain you don’t want to hurt the cat, but the offensive behavior must stop. You want to protect your flowers. Perhaps they will keep their cat inside.
One solution is to sprinkle the beds with a generous amount of black pepper. Cats can’t stand the smell and some will even go into sneezing fits. Don't use cayenne pepper as it may cause harm. Other scents that will keep cats away from your beds are citrus and coffee. Save your orange, lemon and lime peels and scatter them among the plants; the same with coffee grounds. The smell of moth-balls will also repel them as will ammonia.
Cats shy away from water. You can use a water bottle or elaborate motion sprinklers. Cats also have tender paws and will stay away from ground that is rough. Place pinecones, or crushed egg shells in the beds. If you haven’t planted the flowers yet, cover the soil with a fine mesh chicken wire or gravel or even mulch.
Certain plants are a cat deterrent. Among those are marigolds, geraniums, lavender and rue.There are also several commercial, completely organic, products that you pour into the ground that will repel cats.
If all else fails, you may want to think about getting a dog.