Garden Plants That Are Toxic to Cats

A number of common garden plants are actually toxic to cats. When grass is available, most cats will not eat outside plants or flowers. Occasionally, out of boredom or curiosity, a cat may nibble on a leaf or stem. While it's rare that a cat will consume a large enough amount to become ill, it's better to be safe and know which plants are potentially harmful and by what degree. Some may cause kitty just a little discomfort, and other plants can be lethal.

The plants outlined are some of the more popular plants that can harm your cat. This is not an exhaustive list and you'll also want to refer to the ASPCA's toxic plants list to ensure your pets stay safe in the garden.

If you believe your cat has eaten any of these and is showing signs of being sick, contact your veterinarian or call the Animal Poison Control Center immediately.

Azaleas are a member of the Rhododendron family. All plants in this family are moderately toxic to cats, including all parts of the plants. According to The Purdue College of Veterinary Medicine "pets may nibble or taste the leaves out of curiosity or boredom, and this is not advised, but seldom leads to clinical toxicosis."

The ASPCA Poison Control Center is more guarded about these types of flowers and warns against pet owners planting them in their garden. The clinical signs of consumption include vomiting, diarrhea, hypersalivation, weakness, coma, hypotension, central nervous system (CNS) depression, cardiovascular collapse, and death.

Chrysanthemums (also simply called mums) are popular perennials that provide a lovely burst of fall color. There are a variety of chrysanthemum species—including common daisies—whose leaves and stems are poisonous to both cats and dogs.

Cats who ingest those parts of the plant may vomit, drool, or get diarrhea. You can also look for signs of depression and a lack of appetite. 

The daffodill (also known as narcissus, jonquil, or paper white) is the traditional harbinger of spring, right alongside tulips, which are also poisonous to cats. While they are beautiful, these pretty flowers (along with the stems and leaves) can cause upset tummies, vomiting, diarrhea, drooling, or depression if consumed by your cat.

When it comes to plants grown from bulbs, including daffodils and tulips, it is the bulb that is most toxic to pets. If you have these in your garden, you might need to take measures to discourage your cat from digging up the bulb.

Hydrangeas are found in many home gardens because of their beauty and immense popularity as dried flowers in arrangements. Their toxicity level to cats is low and may result in stomach pains, vomiting, and weakness if the flower heads are ingested. Be sure to keep the flowers out of your cat's reach even when drying them.

Irises are favorite flowers in old-fashioned gardens, where they were once known as "flags." They are fairly safe to use in gardening, once planted. It's the rhizomes (the creeping root stalks) that are actually toxic to felines, causing typical gastrointestinal symptoms.

Take precautions if your cat (or dog) likes to dig. It may also be wise to keep your cat inside while you transplant or divide irises.

Ivy is commonly used as ground cover or for shade, as in covering gazebos or trellises. It's also a popular house plant. Many species of ivy—including the popular English Ivy and ivy arum (or pothos)—are considered moderately toxic to cats.

These plants can cause gastrointestinal symptoms and burning or irritation in the mouth, along with breathing difficulty, coma, or even death, if a sufficient amount of leaves is ingested. The berries are not as poisonous to cats, though they're not safe, either.

Lilies come in many varieties and all look quite different from each other. As popular as they are, unfortunately, these flowers are on the "least wanted" list of plants in a garden for cats. Ingesting any part of the plant can cause kidney failure and ultimately lead to death.

This precaution also applies to other "lily" plants, including lily of the valley and both the orchid and bush that go by that name. To be safe, it's best to avoid any plant with lily in its name.

Marigolds are sturdy, perky little annuals. They are colorful and exceptionally easy to grow, which is why they're so popular. Their pungent aroma helps keeps insects at bay and they are commonly planted near roses to deter aphids. If your cat eats marigold leaves or stems, they may suffer from mild mouth irritation, possible drooling, tummy pain, and diarrhea. Contact from the plant's sap may also cause skin irritation.

Wisteria is naturally a vine, but it has been trained to grow as trees by some horticulturists. The seeds and pods are the toxic part that should be a concern to pet owners. Cats who eat these may experience vomiting (which may be bloody), as well as diarrhea, dehydration, and depression.