What plants are poisonous to cats and why?

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Cats love to chew plants. Our pets also enjoy climbing on plants, hiding in them, and jumping out from behind them.  

Fortunately, many beautiful flowers and tasty herbs do no harm to cats. Contrary to popular lore, you can be a pet parent and a plant parent without putting your cats at risk. 

Some plants can poison cats, however. The trick is to know which plants to bring home and which ones to leave at the nursery. What plants will perk your home and your kitty? And which household plants are toxic to cats?

Let's dig into the question of cats and houseplants.

Household plants that won't harm your cat.

PureWow offers a list of 31 plants that are not toxic to cats. These include attractive options such as the hibiscus, impatiens, Boston ferns, spider plants, roses, and sunflowers. The ASPCA offers an even more exhaustive list of non-toxic plants for cats. They also maintain a similar list for dogs and one for horses. 

Something to keep in mind if you have both a cat and a dog — some plants that are fine for cats may harm dogs, and vice versa. Be sure to carefully read both lists carefully and choose greenery that will be safe for all your household pets.

What part of a plant is actually poisonous to cats?

All parts of a toxic plant can be poisonous to cats. In the daffodil, for instance, the heads and leaves can make a cat sick, but the bulb can cause death. All parts of a lily are dangerous. 

Be careful even of bouquets because some plants — such as the aforementioned lily — contain pollen that can harm your cat. In fact, pollen is especially harmful because cats don't notice they're carrying it.

Fortunately, though, most cats are wary of snacking on a plant they don't recognize and will give a wide berth to anything poisonous. Surprisingly few cats show up at vets' offices with plant poisoning. Those that do often have mild cases and appear to have transferred pollen to themselves while grooming. 

Symptoms of plant poisoning in cats.

How do you know if your cat has ingested something poisonous? Signs of plant poisoning include:

• Twitching
• Diarrhea
• Drooling
• Seizures
• Collapse
• Difficulty breathing
• Sneezing
• Poor appetite
• Vomiting
• Confusion
• Depression
• Lethargy
• Coma
• Irritated skin, eyes, or gums

Treatment and care for a poisoned cat.

If you suspect your cat has been poisoned, you should act immediately. 

First, remove the plant so none of your pets can ingest any more of it. Second, write down the time you noticed your cat became ill and the kind of plant you believe the animal consumed. Then, call your cat-friendly vet. 

Follow the advice your vet gives you, which could include taking the animal to the clinic. In this case, you may also need to bring along the offending plant and a sample of your pet's vomit if applicable.

Now, let's explore what plants are toxic to cats.

What plants are poisonous to cats?

Autumn Crocus
The autumn crocus' scientific name is colchicum autumnale. Sometimes called the "meadow saffron," this plant is not actually a crocus at all. It's part of a group of fall-flowering bulbs that fall within the lily family. 

The autumn crocus is very poisonous to both cats and dogs. Signs your pet may have been poisoned by this plant include shock, diarrhea, bloody vomiting, multi-organ damage, and bone marrow suppression.

Azalea and Rhododendron
Azaleas and rhododendrons look very similar and both belong to the same genus, which is also called rhododendron. These plants flower in the spring and are beloved by gardeners and landscapers across the U.S.

Unfortunately, these beauties can poison both dogs and cats. Signs a cat has been poisoned by an azalea or rhododendron include diarrhea, vomiting, weakness, and cardiac failure. 

Daffodil
Sometimes called the narcissus or the jonquil, these are some of the most poisonous plants for cats. Daffodils have six petals surrounded by a trumpet-shaped corona. Most often, the flowers are yellow and white although they can be orange or pink. The plant's bulbs are its most poisonous part.

Daffodils are toxic to both cats and dogs. Signs your pet may have been poisoned by a daffodil include diarrhea, vomiting, and salivating. Ingesting a large amount may cause tremors, convulsions, low blood pressure, or cardiac arrhythmias.

Oleander
Oleander is a large shrub or small tree noted for its white, pink, or red blooms that often give off a sweet scent. In the U.S., oleander grows best in warm climates such as Florida, California, and the southern states.

Oleander is toxic to both cats and dogs. Signs of poisoning include colic, diarrhea, depression, abdominal pain, drooling, and death. Incidentally, oleander is also poisonous to humans, and ingesting a single leaf can kill an adult. 

Kalanchoe (Mother-in-Law Plant)
Kalanchoe delagoensis goes by several common nicknames such as mother-in-law plant, devil's backbone, chandelier plant, and mother of millions. This succulent plant, which originated in Madagascar, is now a popular houseplant, probably because it sometimes blooms in winter.

Kalanchoe delagoensis is poisonous to both cats and dogs. The clinical signs of poisoning from this plant include diarrhea and vomiting and (rarely) an abnormal heart rhythm.

Hyacinth
A bulbous plant native to the Mediterranean, the hyacinth is noted for its three spikes of thick, brightly colored flowers. Despite the plant's beauty, hyacinth bulbs can be moderately poisonous to humans, and gardeners would be wise to wear gloves when handling them to avoid skin irritation.

Hyacinths are poisonous to both cats and dogs. Hyacinth poisoning may result in depression, tremors, intense vomiting, or diarrhea occasionally with blood.

English Ivy
A rampant vine, English ivy grows in many gardens, lawns, and waste spaces. This hardy plant can cover a fence, a tree, a rock garden, or the side of a house. Although English ivy is an ornamental plant that can attract many pollinators, this plant can grow wild and cause damage to property if left unchecked.

English ivy is toxic to both dogs and cats, and it's foliage is even more poisonous than its berries. Clinical signs of poisoning from English ivy include diarrhea, vomiting, hypersalivation, and abdominal pain. 

Lily
One of the most toxic plants for cats, the lily is a well-known spring or summer flower because of its beauty and sweetness. Potted lilies make popular gifts around Easter. Scientists still aren't sure why lilies are so poisonous to cats, but they do know the poison affects the urinary system. Cats can go into kidney failure from ingesting even the pollen of a lily.

Lilies are not toxic to dogs, but they can cause serious damage to cats. If you suspect your pet has had contact with a lily — even if they have just brushed against it — contact your vet at once. 

Cyclamens
A perennial plant that flourishes in autumn and winter, cyclamens (sometimes called sowbread) feature variably patterned leaves and upswept petals. This plant also has a pod, which is filled with seeds usually distributed by ants. 

Cyclamens are poisonous to both dogs and cats. Signs of toxicity include diarrhea, vomiting, and salivation. Ingesting large amounts of tubers can cause seizures, heart rhythm abnormalities, and ultimately death.

Morning Glory
Morning glories aren't just one kind plant. The name actually refers to about 1,000 species of a flowering plant that usually unfurls its blooms in the morning before closing for the afternoon and evening. Hardy and fast-growing, morning glories thrive under nearly any conditions.

These plants are poisonous to both cats and dogs. Ingesting morning glories generally results in vomiting, but eating a lot of seeds may also cause hallucinations.

Tulips
Tulips have been cultivated since the 10th century, and it's easy to see why. Showy and brightly colored, tulips make the perfect spring flower. These bulbous plants are popular and easy to grow, which has led to many tulip festivals around the world. Humans can eat tulips with no ill effects, and in fact, during the 1944-45 famine in the Netherlands, tulip bulbs were a popular food.

These plants are toxic to both dogs and cats, however. Tulip poisoning can result in vomiting, diarrhea, depression, or hypersalivation.

Aloe
Though most people may be familiar with the aloe vera plant, aloe actually refers to an entire genus that consists of about 560 succulent plants. Their thick, fleshy leaves make aloe popular as an ornamental plant in gardens and pots. Many people keep aloe vera since it can treat first and second degree burns.

Toxic to both cats and dogs, aloe can cause vomiting and diarrhea. Interestingly, the gel is non-toxic to animals.

Daisy
Daisies are easy to recognize by their bright yellow central discs surrounded by rays of white florets. These flowers make excellent groundcovers in cottage or English gardens. Charming and sweet, the daisy doesn't look like one of the toxic plants for cats, but it can cause serious damage. 

These plants can poison both cats and dogs. Clinical signs of daisy poisoning in animals include dermatitis, incoordination, vomiting, diarrhea, and hypersalivation.

While household pets can interact safely with many plants, it's a good idea to double check any flower or fern you plan to purchase against an exhaustive list of toxic plants for cats. We want to keep our pets healthy and happy.