Answer: So what you're saying is that your cats pretty much rule the house! I found that persistent training worked: sharply spoken "NOs" and a squirt of water.
Also, I suggest you grow some grass just for your cats to eat. Many cats love to chew on grass (perhaps it aids in digestion). They love oat grass, wheat grass, barley, etc. (My cat's favorite is oat.) You can buy little containers at pet stores. Or, buy the unsprouted grain at natural food stores. Plant it in a soilless seed starting mix, keep moist, and place in sun. With very little training and encouragement, my cat learned the grass is hers; the spider plant is mine! Good luck!
Here are two websites that list poisonous plants.
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