11 Surprisingly Common Plants That Are Poisonous to Pets

Written and submitted by guest author, Emily Jackson

Most pet owners know that some plants, including lilies, poison ivy, azalea, daffodil, and oak, are harmful to their cats and dogs. However, you may be shocked to find out that we are surrounded by surprisingly common house plants that are poisonous to pets.

This article goes into detail on some of the common house plants poisonous to pets, so you know what to look out for around the house and in the garden. With so many potentially dangerous and poisonous plants for pets around, we’d always recommend practicing care when planting particular veggies, herbs, and flowers in your garden or windowsills to protect your beloved furry friends. If you can't live without some of the listed plants, be sure to supervise your animals carefully, especially curious cats.

Common Plants Poisonous to Pets

1. Aloe Vera: A Common Household Plant Toxin

Among the most surprising is Aloe Vera, known as a plant highly beneficial for humans. While the plant’s internal gel is mostly harmless, its skin is toxic to both cats and dogs. Chemicals, saponins (glycosides), located in the skin of the leaf have antiseptic and cleansing properties in humans. Alternatively, these chemicals can cause vomiting, diarrhea, tremors, depression, lethargy, and extremely irritated skin in your pet.

Fortunately, symptoms are usually not severe, unless your pet ingests a large piece of the plant. If you spot red urine along with other symptoms, take your pet to the vet right away.

Symptoms To Look Out For:

  • Vomiting

  • Lethargy

  • Diarrhea

  • Tremors

  • Red urine

  • Depression

  • Increased skin irritation

2. Hibiscus: What Pet Owners Need to Know

While many hibiscus varieties are considered safe, some types of hibiscus can be poisonous to pets. The Rose of Sharon (Hibiscus syriacus) is particularly concerning for pet owners, as this hibiscus variety can be toxic to both cats and dogs.

Hibiscus Toxicity For Dogs:

  • Most common hibiscus varieties are generally safe

  • Rose of Sharon can cause digestive issues if ingested

  • Symptoms include nausea, diarrhea, and vomiting

  • Severity depends on amount consumed

Hibiscus Toxicity For Cats:

  • Both blossoms and stems of Rose of Sharon are poisonous

  • Can cause digestive upset and discomfort

  • Monitor cats around all hibiscus varieties

  • Remove fallen flowers and leaves promptly

If you're growing hibiscus in your garden or home, take these precautions for your pet:

  • Research your specific hibiscus variety before planting

  • Keep indoor hibiscus plants out of pets' reach

  • Clean up fallen flowers and leaves regularly

  • Consider fencing off garden hibiscus plants

  • Watch for signs of plant chewing or ingestion

Symptoms To Look Out For:

  • Vomiting

  • Diarrhea

  • Loss of appetite

  • Lethargy

Contact your veterinarian immediately if you suspect your pet has consumed toxic hibiscus parts. While most cases are mild, prompt treatment ensures the best outcome for your pet.

The Rose of Sharon hibiscus is beautiful but toxic to pets

Frequently Asked Questions About Hibiscus and Pets

Are all hibiscus plants poisonous to cats and dogs?

No, not all hibiscus plants are poisonous. While most common hibiscus varieties are considered non-toxic, the Rose of Sharon (Hibiscus syriacus) can be harmful to both cats and dogs. For dogs, ingestion can cause digestive issues, while for cats, both the blossoms and stems can be poisonous.

What happens if my dog eats hibiscus flowers?

If your dog eats Rose of Sharon hibiscus flowers, they may experience nausea, diarrhea, and vomiting. Most cases are mild, but the severity depends on how much was consumed. Other hibiscus varieties typically cause minimal to no issues.

Are hibiscus leaves toxic to pets?

The leaves of most hibiscus varieties are generally safe, but Rose of Sharon hibiscus leaves can cause digestive upset in both cats and dogs. For cats, the leaves pose a higher risk than they do for dogs.

3. Oleander: A Beautiful but Dangerous Flower

Oleander is extremely toxic to dogs, cats, horses, and even humans and even small amounts may cause several significant health issues. Though Oleander primarily grows in California and Hawaii, it has been growing in popularity across the USA thanks to its gorgeous flowering appearance, so it’s definitely one to look out for if you have it around the home or are thinking of adding it to your collection.

What Parts Of Oleander Plants Are Toxic To Pets?

Although for most pets Oleander is unattractive, some are still curious about it and may try to sniff, lick, or rub against it if it is in the home or the garden so it is important for pet owners to know that all parts of the plant are highly toxic including:

  • Leaves

  • Flowers

  • Stem

  • Sap

What Side Effects Can Oleander Plants Lead To?

If your pet comes into contact with or ingests Oleander, you should seek immediate veterinary care. Some of the side effects to look out for include:

  • Drooling

  • Vomiting

  • Diarrhea

  • Abnormal heart rate or arrhythmias

  • Tremors

  • Seizures

  • Collapse

In rare cases, it can lead to death. While this is uncommon, it speaks to the importance of seeking immediate care for your pet if you suspect they have had contact with the plant.

4. Philodendron (Including Heartleaf & Split-leaf varieties)

Philodendrons are among the most popular houseplants in Charlotte homes, favored for their low maintenance and ability to thrive in humid indoor environments. Unfortunately, they pose a serious risk to curious pets.

For Philodendrons, all parts of the plant are toxic including leaves, stem, and roots, and chewing or biting into any portion of the plant can release the oxalate crystals (the toxic compound in the plant) and cause immediate oral irritation.

Philodendron Toxicity Symptoms To Look Out For

  • Drooling

  • Oral pain and pawing at the mouth

  • Swelling of lips, tongue, and throat

  • Vomiting

  • Difficulty swallowing or breathing in more severe cases

If you think your pet may have chewed on or ingested any part of a Philodendron plant, seek immediate veterinary attention.

5. ZZ Plant (Zamioculcas zamiifolia)

The ZZ Plant has become a darling of modern interior design in Charlotte and beyond — admired for its sculptural shape, glossy dark green leaves, and near-indestructibility. However, this plant is toxic to pets, and its beauty hides a chemical defense system that can cause unpleasant symptoms if touched or ingested.

Similar to Philodendrons, all parts of the ZZ plant are toxic to pets including the leaves, stem, and roots, and chewing or ingesting any part of the plant can release the toxins.

ZZ Plant Toxicity Symptoms To Look Out For

  • Drooling

  • Oral pain and pawing at the mouth

  • Vomiting

  • Diarrhea

  • Loss of appetite

  • Mild skin irritation (especially around the mouth or paws)

6. Sago Palm (Cycas revoluta)

Despite its name, the Sago Palm is not a true palm — and it's far more dangerous. This plant is extremely toxic to pets, and ingestion can be fatal, even in small amounts. Unfortunately, it’s sometimes sold as a decorative indoor or patio plant so is commonly found around the home.

What Parts Of A Sago Palm Plant Are Toxic To Pets?

All parts of the plant are toxic, but the seeds (nuts) are the most poisonous and most likely to attract pets. Even a single seed can be life threatening, so it is extremely important to monitor your pets around this plant and take extra precautions to prevent any harm.

Sago Palm Toxicity Symptoms To Look Out For

  • Vomiting (often severe or bloody)

  • Diarrhea

  • Lethargy

  • Loss of appetite

  • Abdominal pain

  • Jaundice (yellowing of skin or gums)

  • Seizures

  • Liver failure

  • Death if not treated quickly

Given the severity of issues likely to occur if your pet comes into contact with a Sago Palm plant, we strongly advise pet owners to take extra precautions if you know you have this plant at home or are going to be in a location where they grow. If your pet does ingest or chew any part of a Sago Palm plant, seek immediate veterinary attention.

7. Snake Plant / Mother-in-Law’s Tongue (Sansevieria trifasciata)

The Snake Plant is another favorite for low-maintenance houseplant lovers in Charlotte. It tolerates neglect, low light, and infrequent watering, but it poses a mild to moderate risk for pets if ingested so it is important to stay vigilant and keep an eye on pets if you have this plant at home.

What Parts Of Snake Plants Are Toxic To Pets?

All parts of the plant are toxic, especially the stiff, upright leaves, which are the most likely to be chewed. The sap can also cause mild skin irritation in some pets.

Snake Plant Toxicity Symptoms To Look Out For

  • Nausea

  • Vomiting

  • Diarrhea

  • Lethargy

  • Drooling (in some cases)

Other Common Plants Poisonous To Pets

As well as the plants listed above, there are a number of other common plants that are poisonous to pets but are often found in and around the home, including:

Potatoes: An Unexpected Kitchen Danger

Recently, the FDA (the US Food and Drug Administration) announced that DCM (canine dilated cardiomyopathy) was reported in dogs eating pet food containing potatoes and peas as primary ingredients.

This disease usually occurs in genetically prone breeds. However, veterinarians have discovered that a wide variety of dogs may become sick after eating food rich in this particular vegetable for long periods of time. Many common varieties of grain-free dog food are found to contain high quantities of potatoes.

Both potatoes and their stems/leaves contain highly toxic solanine that is poisonous to your pets. You should never feed a dog raw potatoes, and while cooking will reduce the level of this chemical, potential risks still exist. Instead, consider replacing standard potatoes with dog-approved, cooked sweet potatoes.

Oregano: Hidden Herb Hazard

Many of us grow oregano (Origanum vulgare hirtum) in our homes and gardens, but rarely are pet owners aware of how dangerous this particular plant is for their furry friends. Thankfully, nature stepped in to make this plant repellent to cats. Their sophisticated noses sense this fragrance at a level 1400% stronger than humans. The consumption of fresh oregano usually causes mild intestinal issues in both cats and dogs.

Additionally, the essential oil made of this plant contains gastrointestinal irritants, such as terpenoids and phenols. Avoid applying this oil to your cat directly since it is poisonous and its ingestion may lead to liver failure.

Tomato Plant: A Garden Safety Concern

Common tomatoes (Lycopersicon spp) and its entire plant are poisonous for both cats and dogs. The unripe fruit, stems, and leaves contain alpha-tomatine and the same glycoalkaloid solanine as potatoes. These parts of the plant may cause intoxication when eaten in a considerable amount. Fortunately, poisoning by tomato plant is not typically fatal.

Common symptoms include weakness, drowsiness, stomach pain, slow heart rate, and difficult breathing. Ripe tomato fruits themselves won't cause any problems in most cases.

Marijuana: The Pet Exposure Risk

Pet poisoning by marijuana (Cannabis sativa) is one of the most common intoxications seen in veterinary practice, especially in dogs. Due to an increased level of cannabinoid receptors in the canine brain, they are particularly vulnerable. For both cats and dogs, most are exposed by nibbling dried leaves, consuming edibles and/or inhaling second-hand smoke.

In Colorado, a state with legalized marijuana, within five years, two veterinary hospitals noticed that the frequency of marijuana poisoning in dogs has increased four times since the legalization legislation was passed.  

Ingesting these plants in any form may cause depression of the central nervous system and problems with coordination in your pet. In most cases, the animal will experience dilated pupils, increased heart rate, troubles with regulating temperature, vomiting, diarrhea, seizures, tremors, and even coma.

Keeping Your Pets Safe

While this list covers some of the most common household plant dangers, it's just the beginning. The ASPCA (The American Society for the Prevention of Cruelty to Animals) maintains comprehensive lists of plants poisonous to both cats and dogs, and we strongly encourage all pet owners to familiarize themselves with these resources before bringing any new plants into their homes or gardens. Take time to identify and research the plants already in your space—you might be surprised by what hidden dangers are lurking on your windowsills or in your yard.

If you suspect your pet has ingested something harmful, don't wait to see if symptoms develop. Contact your veterinarian immediately or call the ASPCA Animal Poison Control Center at (888) 426-4435. Remember, when it comes to plant toxicity, prevention through education is your pet's best protection, and quick action can make all the difference in ensuring your furry family members stay happy and healthy.

About the Author

My name is Emily Jackson. I am a writer, translator, veterinarian, humanitarian, and a passionate traveler. After playing with white bears and elephants in the Belgrade ZOO and dealing with Rabies virus in the Institute Pasteur, I enjoy writing. My five beasts are my ultimate love, including three cats (Clementine, Josephine, and Sophio) and their 'mom' American Stafford Terrier (Malena).