Learn which plants thrive in your Hardiness Zone with our new interactive map!

Outdoor Plants That Are Poisionous to Dogs

By Elizabeth Tumbarello ; Updated September 21, 2017
Avoid letting your dog eat unfamiliar plants.
potato plants image by aprilira from Fotolia.com

Outdoor gardening plants provide beauty and color, yet some can be toxic, even lethal, to our canine companions. It is important to learn which plants are potentially harmful. If you suspect your dog has ingested a poisonous plant, speak to a licensed veterinary medical professional immediately. Bring a sample of the plant with you, if possible, to aid in identification and treatment.


a spring yellow buttercup image by Maria Brzostowska from Fotolia.com

Buttercups are flowers of the genus Ranunculus. These flowers are bright yellow or white with yellow centers. They grow throughout the spring months, usually as a wild flower, though some are cultivated for ornamental purposes. Also known as butter cress or figwort, buttercups are toxic to dogs, according to the American Society for the Prevention of Cruelty to Animals (ASPCA) Poison Control Center website. They contain the toxic principle protoanemonin, a powerful irritant produced when the plant is handled or crushed. When ingested, buttercups produce vomiting, diarrhea, severe gastrointestinal upset, stomach pain, depression, lack of appetite, drooling and ataxia.


daffodils image by leafy from Fotolia.com

Daffodils are members of the Narcissus genus. Known also as jonquil, paper whites and narcissus flowers, these spring-blooming plants derive from bulbs. The flowers come in colors ranging from yellow to orange to red. Daffodils grow wild but are commonly grown for ornamental purposes in gardens. Daffodils are toxic to dogs, according to the ASPCA Poison Control Center website, and contain the active toxic principle lycorine. Lycorine is an alkaloid that stops the body from producing essential proteins. Ingestion of any part of a daffodil is considered extremely dangerous, though the majority of the toxin is contained within the plant's bulb. When eaten by dogs, daffodils produce vomiting, hyper-salivation, diarrhea and stomach pain. Convulsions, reduced blood pressure, seizures, tremors and cardiac arrhythmia and arrest are also possible.


Purple irises
IRIS image by JP65 from Fotolia.com

Iris plants are dangerous to dogs, according to the ASPCA Poison Control Center website. The plants are known for their flowers, which come in every color of the rainbow and have a bearded appearance. These brightly flowering plants are members of the Iris genus and also are called snake lilies or water flags. They contain the active toxic principles zeorin, missourin and missouriensin, which are categorized as pentacyclic terpenoids. The pentacyclic terpenoids contained in irises inhibit the production of enzymes in a dog's body. The entire plant is toxic, though the highest concentration of poison is in the rhizome, or root stalk of the plant. Ingestion causes hyper-salivation, vomiting, diarrhea, nausea and stomach pain.


About the Author


Elizabeth Tumbarello has been writing since 2006, with her work appearing on various websites. She is an animal lover who volunteers with her local Humane Society. Tumbarello attended Hocking College and is pursuing her Associate of Applied Science in veterinary technology from San Juan College.