Does your cat like to nibble on your plants? Perhaps supplying him with a plant of his own to satisfy his appetite will help solve the problem.
Oat seed is very easy to grow and cats may actually prefer it to your plants. Choose a small pot and fill it 3/4 full with regular potting soil. Place 10-15 oat seeds on the surface, cover with soil, water, and keep in a warm, dark place for a few days until the seeds germinate. Keep the plants in full light and away for the cat until the blades are about 4 inches high. It might be a good idea to keep a continual rotating series of pots so your kitty can nibble to his/her hearts content.