Plant Toxicity and Pets

plant in orange pot with holes in leaves and example of high plant toxicity

Common houseplants like Philodendrons can have a high plant toxicity rating.

Plants Are Devious

We don’t often think about plant toxicity when choosing plants for our home or landscape. However, the plant world includes some very creative defense mechanisms against pests and browsers.

These defenses range from physical barriers like thorns to deadly poisons. To complicate matters, one part of a plant may be edible while another is highly toxic. You must also consider the physiology differences between humans and our animal companions. Chocolate, for example, is a great treat for a human but a highly toxic substance for a dog.

There are some great resources to help you navigate whether or not a plant should be included in your home or landscape. We’ve included a chart to get you started that has been compiled from information provided by J.S. Lee, DVM,DACVECC,DABT via the Veterinary Information (


Plants with Calcium Oxalate Crystals – Toxic to Both Dogs and Cats

Common Name

Botanical Name


Arrowhead Vine Syngonium podophyllum These plants contain microscopic needle- like calcium oxalate crystals which irritate the mouth and throat of the animal when they chew the plant. This causes drooling, swelling of the face and lips and even difficulty breathing. First aid includes removing the plant material, flushing the mouth with water, and then offering broth, tuna juice or other appealing fluids to help flush the crystals from the mouth. Always call your veterinarian if ingestion is suspected.
Calla Lily Zantedeschia aethiopica
Devil’s Ivy Epipremnum aureum
Dumb CaneHouseplant with blotchy leaves Dieffenbachia seguine
Elephant’s Ear Colocasia esculenta
Philodendron Philodendron spp
Pothos Epipremnum aureum
Mother-in-law’s Tongue Dracaena trifasciata
Umbrella Plant Cyperus alternifolius
Star Fruit Averrhoa carambola Because of their action on calcium in the body, ingestion of these plants in large amounts can cause vomiting, diarrhea, drooling, and progress into tetany and kidney damage. Induction of vomiting activated charcoal and fluid therapy are required as treatment. Always call your veterinarian if ingestion is suspected.
Rhubarb leaves Rheum rhabarbarum
Shamrock plant Oxalis spp

For a list of plant toxicity ratings, please visit the American Society for the Prevention of Cruelty to Animals® (ASPCA®) Toxic and Non Toxic Plant List.

Lilies Especially Toxic for Cats

Common Name

Botanical Name


Easter Lily Lilium longiflorum All parts of these plants, even the pollen and the water that cut flowers rest in, can be fatal for cats. Signs will start with vomiting and depression and can progress to kidney failure within 3 days.  Immediate hospitalization is necessary, Call your veterinarian immediately.
Tiger Lily Lilium lancifolium
Japanese Show Lily Lilium speciosum
Stargazer Lily Lilium orientalis ‘Stargazer
Rubrum Lily Lilium speciosum var. rubrum
Day Lily Genus Hemerocallis

Please visit the ASPCA® Toxic and Non-Toxic Plant List – Cats for more plant toxicity ratings.

Plants Especially Toxic for Dogs

Common Name

Botanical Name

Peace Lily Genus Spathiphyllum
Calla Lily Zantedeschia aethiopica
Lily of the Valley Convallaria majalis
Autumn Crocus Colchicum autumnale
Dracaena Genus Dracaena
Palm Lily Cordyline fruticose

Please visit the ASPCA® Toxic and Non-Toxic Plant List – Dogs for more plants and their toxicity rating.

Toxic Flower Bulbs

Common Name

Botanical Name


Daffodils Narcissus genus The toxic agent of the above plants is found in the bulbs, not the flowers or foliage. Small amounts cause gastrointestinal upset, but large amounts of daffodil bulbs can affect the heart and nervous system. With small amounts of tulip and hyacinth ingestion, vomiting and diarrhea are typical but large amounts of these plants can result in heart, breathing and skin problems.
Tulips Tulipa genus
Hyacinths Hyacinthus genus


Additional Resources for Pet and Livestock Owners

American Society for the Prevention of Cruelty to Animals® (ASPCA®) Poison Control Center

Poisonous plants list – ASPCA:

ASPCA Toxic and Non-Toxic Plant List – Dogs:

ASPCA Toxic and Non-Toxic Plant List – Cats

Earth-Kind Landscaping Common Poisonous Plants and Plant Parts

University of Vermont Extension Poisonous Plants

Houseplants for Central Texas

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