Dear Christopher Cat: We live in the country, and our cats enjoy venturing outdoors on nice days. As I plan my garden, how can I avoid plants that are toxic to cats? Christopher Responds: Many plants are toxic to pets, including chrysanthemums, clematis, coleus, daffodils, geranium, hibiscus, hosta, hyacinths, most ivies and lilies, peony, sweet William, tulips and vinca. You ask about pet-safe plants, but you also should ensure the safety of other elements of your garden. For example, cocoa mulch is toxic if ingested, because it contains theobromine and caffeine, which can cause vomiting, diarrhea, elevated heart rate and seizures. Use a mulch of hardwood or pine instead. Insecticides and herbicides can pose problems too. Research on phenoxy-type herbicides shows they increase the incidence of cancer. Non-phenoxy herbicides, such as Roundup, do not increase cancer risk. Don’t use slug bait that contains metaldehyde, which can be fatal to pets and wildlife. Check the Internet or your cooperative extension service for safe alternatives. For a comprehensive list and photos of pet-safe garden plants, visit the Animal Poison Control Center. Finally, don’t forget to plant catnip, cat thyme and cat grass for your kitties.