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The Most Toxic Plants for Cats and Dogs

Every year, pets are poisoned by common plants — houseplants, garden shrubs, even cut flowers. Here are the most dangerous ones, ranked by severity, with symptoms and what to do.

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⚠️ The deadliest (life-threatening)

Lily (Lilium)Highly toxic

The #1 plant to keep away from cats. Every part — even pollen and vase water — can cause fatal acute kidney failure. No amount is safe. Suspected contact is an immediate veterinary emergency.

Lily of the Valley (Convallaria)Highly toxic

The whole plant contains cardiac glycosides: heart-rhythm abnormalities, vomiting, convulsions. A pretty flower that is genuinely dangerous.

Oleander (Nerium)Highly toxic

An extremely toxic garden shrub — a single leaf can be enough. Severe, potentially fatal cardiac effects in both dogs and cats.

Yew (Taxus)Highly toxic

A classic garden hedge but a serious hazard: needles and seeds cause severe arrhythmias and sudden death.

Sago Palm (Cycas)Highly toxic

A trendy houseplant. The seeds especially cause liver failure, often fatal in dogs.

Foxglove (Digitalis)Highly toxic

A beautiful garden flower and a powerful heart poison. Ingestion causes arrhythmias, vomiting and severe lethargy.

🟠 Very common houseplants (moderate)

Dieffenbachia, Philodendron, MonsteraModerately toxic

The houseplant trio. Insoluble calcium oxalate crystals cause intense mouth burning and irritation, drooling, difficulty swallowing. Rarely fatal but very painful.

Pothos (Epipremnum), Chinese Evergreen, AlocasiaModerately toxic

Same oxalates: oral and digestive irritation. Keep out of reach of pets that like to chew.

Bulbs: Tulip, Daffodil, HyacinthModerately toxic

The bulb is the most concentrated part: vomiting, diarrhea, sometimes cardiac effects. Watch dogs that dig.

What to do if your pet eats one

1. Don't wait for symptoms. Call your vet or ASPCA Animal Poison Control (888-426-4435) right away.
2. Identify the plant (name or photo) and note the amount and time.
3. Do not induce vomiting without veterinary advice — for some plants it's dangerous.

Check before it's too late

Leafy identifies any plant from a photo and tells you whether it's safe for your pet — sources shown, free.

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👉 See also: the full list of plants toxic to cats & dogs · pet-safe plants.

⚕️ This is general reference information, not veterinary advice. Pet toxicity is partly referenced from the ASPCA toxic-plant list (reformulated) and Leafy's botanical database. In an emergency, contact a professional.