Some cats have this attraction to just leaves while others are. Select a Safe Cat Litter Attractant Dr. All cats whether they live outdoors or indoors love the contact with greenery when the first one eats the grass in the garden the second one nibbles on the plants in the living room beware of intoxication.
Its surmised to imitate feline pheromones and set off the cats receptors. Incidentally in herb lore catnip is believed to be an aphrodisiac and is often used in love charms. This is why you should limit the use to once a week. Everyone knows cats go crazy for catnip.