Poisonous plants for pets

February 8, 2019

Over the years, the CJGs team has heard a few gardening horror stories, and you may be surprised to learn that a lot of these are to do with our furry friends!


We’ve often been asked by dog and cat owners’ things like “My cat ate a lily!” or “My dog ate a plant. Is it poisonous?”


So, as pet lovers ourselves (some of you may know the lovely Teds the Rottweiler as part of the CJG’s team), we thought we’d make you aware of some of the most poisonous plants for dogs and cats.


While there are thousands of species of plants and flowers, only a small percentage of plants are truly dangerous and poisonous to pets. Make sure you know which plants are most deadly so you can try and avoid dogs or cats from getting into these poisonous flowers and plants at your home or the office!


Autumn Crocus

There are two Crocus plants: one that blooms in the spring (Crocus species) and the other in the autumn Colchicum autumnale).


The spring plants are more common and are part of the Iridaceae family. If ingested, these can cause general gastrointestinal upset including vomiting and diarrhoea. These should not be mistaken for Autumn Crocus, part of the Liliaceae family, which contain colchicine.


The Autumn Crocus is highly toxic and can cause severe vomiting, gastrointestinal bleeding, liver and kidney damage, and respiratory failure. Signs may be seen immediately but can be delayed for days.


In the same family as rhododendrons, azaleas can have serious effects on pets. Eating even a few leaves can result in vomiting, diarrhoea and excessive drooling; without immediate veterinary attention, the pet could fall into a coma and possibly die.



The roots of this seasonal flowering plant are especially dangerous to pets. If ingested, cyclamen can cause severe vomiting and even death.



There are dangerous and benign lilies out there, and it’s important to know the difference.


Peace, Peruvian, and Calla lilies contain oxalate crystals that cause minor signs, such as tissue irritation to the mouth, tongue, pharynx, and esophagus – this results in minor drooling.


The more dangerous, potentially fatal lilies are true lilies, and these include Tiger, Day, Asiatic, Easter and Japanese Show lilies – all of which are highly toxic to cats! Even small ingestions (such as 2-3 petals or leaves) can result in severe kidney failure. If your cat is seen consuming any part of a lily, take it to your nearest vet practice immediately!



Oleander is an outdoor shrub, popular for its evergreen qualities and delicate flowers. However, the leaves and flowers are extremely toxic if ingested and can cause severe vomiting, slow the heart rate and possibly even cause death.


Popular in many homes and offices, dieffenbachia can cause intense oral irritation, drooling, nausea, vomiting and difficulty swallowing if ingested.


These flowers contain lycorine, an alkaloid with strong emetic properties (something that triggers vomiting). Ingestion of the bulb, plant or flower can cause severe vomiting, diarrhoea, abdominal pain, and even possible cardiac arrhythmias or respiratory depression.  Daffodil ingestions can result in more severe symptoms so if exposure is witnessed or symptoms are seen, seek veterinary care.

Lily of the Valley

The Convallaria majalis plant contains cardiac glycosides which will cause symptoms including vomiting, diarrhoea, a drop in heart rate, severe cardiac arrhythmias, and possibly seizures. Pets with any known exposure to this plant should be examined and evaluated by a veterinarian and treated symptomatically.

Tulips and Hyacinths

Tulips contain allergenic lactones while hyacinths contain similar alkaloids. The toxic principle of these plants is very concentrated in the bulbs, so make sure your dog isn’t digging up the bulbs in the garden. When the plant parts or bulbs are chewed or ingested, it can result in tissue irritation to the mouth and esophagus. Typical signs include profuse drooling, vomiting, or even diarrhoea, depending on the amount consumed.


If you suspect your pet has ingested any of these items or any other questionable substance in the garden, the best advice is always to check with your vet on the best course of action.


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