These poisonous plants can pose a danger to your pets

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Although many garden and woodland plants are completely harmless for wildlife, there are also some specific poisonous plants which can pose an extreme danger to household pets.

These can be in your garden, in the local park or even in woodland areas, so if you’re taking your dog out for a country walk or letting your cat roam in the garden these plants should be spotted and avoided in order to prevent serious harm.

These are some of the most common plants and trees which can pose a danger to your pet.

Woodland plants:


All parts of a rhododendron bush, including the leaves, stems and blooms, are toxic to both cats and dogs.

Only a small amount of rhododendron is needed to cause health problems if your dog eats any part of this bush and smaller dogs will typically experience more severe, toxic effects than large dogs after eating the same amount of rhododendron.

All parts of the rhododendron are toxic and have the potential of causing serious damage to cats due to their small body size. It is the presence of toxic resins called “grayanotoxins” that make this plant so dangerous.

Dog's Mercury

Dog’s Mercury, also known as Mercurialis perennis, is an indicator species. This means that it helps to date the woodlands that it grows within.

Although not that much is known about the toxic substances within the plant, it is believed that saponins and methylamine are present and it can poison cattle, sheep pigs, goats, horses, dogs and rabbits.


Foxglove contains naturally-occurring poisons that affect the heart, specifically cardenolides or bufadienolides, so when out walking your dog avoid letting them near this wherever possible.

Yew Tree

The Yew Tree is toxic to all animals including cats, dogs, horses and cattle.The entire Yew tree can be toxic to pets if eaten, causing nausea, vomiting, and diarrhea even with the consumption of a small amount of cones, these having the highest concentration of the toxic chemical.

Garden plants:

Lily of the Valley

Both dogs and cats can be poisoned by lily of the valley (Convallaria majalis). All parts of this plant are poisonous, but when it is in flower the strong fragrance attracts pets, hence causing a danger.


Monkshood (Aconitum) is widely planted in herbaceous borders. It offers tall, spike-like deep-blue flowers and is extremely toxic. It can cause poisoning through the contact of the plant juices with the skin of your pet.


Azaleas are in the same family as rhododendrons and can seriously harm pets. Even just a eating a few leaves can result in your pet vomiting, having diarrhea and excessively drooling.

If your pet does come into contact with the plant and doesn’t receive immediate veterinary attention, they are in harm of falling into a coma.

What to do if you suspect your pet has come into contact with a toxic plant

Don’t leave anything to chance. If you suspect your pet has come into contact with a potentially toxic or poisonous plant you should contact your vet immediately for advice and don’t wait for any possible symptoms to develop.

The quicker you get medical attention for your pet, the more likely is the chance of it being treated and its chance of survival.

If plant poisoning is suspected when a pet falls suddenly sick, seek veterinary advice immediately.

Taking a specimen of the plant that has been eaten along with you to the vets will also be extremely useful if this situation does arise.

If possible, be on guard whilst your pet is out and about and avoid leaving clippings lying about and clear up any fallen berries.