I have a lot of plants that I "shouldn't" have around cats. My cat is mostly uninterested, so I consider it safe. If I notice a chomp in a plant or catch him doing it, I keep an eye on him for many days, but have never seen symptoms. I suspect because he never actually eats it. For a lot of plants, as long as the cat doesn't fully chew and/or swallow the plant, there's likely not enough plant in their system to be toxic. But that's not true for all plants (never keep anything in the true lily family), so do your research. Know the plant and know your cat.
That being said, it's still best practice to disallow your cats from even nibbling any plant they shouldn't. Here are some suggestions:
- Keep plants where cats can't get them. This is hard since cats are little magicians, but I keep my plants on middle shelves of bookshelves he's never attempted to get to, or in the kitchen (which he inexplicably hates).
- Have plants the cats can eat. I keep cat grass and catnip in easily accessible places, so if my cat feels the need to chomp, he goes to the plants that taste good and are easy to get to. (Make sure this doesn't end up encouraging your cat to eat ALL The plants.) Both catnip and cat grass are extremely easy to grow from seed, and can be found in most pet stores.
- Check his diet for any deficiencies. Some research suggests cats feel compelled to nom a plant when they're lacking something in their diet. Check with your vet for suggestions.
- Give the cats plenty else to do. As long as the cats are occupied with other things to do, they're less likely to do things they shouldn't. Give them lots of toys to play with and things to climb. Be sure you're spending time with them to get their energy out. They can't eat plants if they're sleeping!
It's best to assume all plants (outside of cat-intended plants) are bad. So give them alternates, and discourage all other types of plants.
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