What Plants Are Poisonous to Dogs? 10 Plant Profiles

The following plants are poisonous to dogs- Philodendron, Oleander, Japanese Yew, Lilly of the Valley, Autumn Crocus, Cyclamen, Sago Palm, Dieffenbachia, Rhododendron, and Tulips, to name a few of the most popular houseplants.

As a horticulturist and owner of a rescue dog that has suffered from toxic poisoning, I ensure dangerous plants don’t surround my pets. My dog spends most of her time in the garden and often likes to chew grass growing under the trees. I am not one to watch her every move, so eliminating any risks of her eating something she shouldn’t be will save me time, possibly her life and money on hefty vet bills in the long run.

I’ve already mentioned a few poisonous plants to dogs, but I want to share a lot more information. Along with this also I will share what signs to look for if you are worried your dog has ingested any of the toxic plants.

dog legs with a growing plant

Table of Contents

Philodendron Leaves Can Be Dangerous

With its heart-shaped leaves, it is a common houseplant among plant lovers. As beautiful as it may seem, it contains an irritant called calcium oxalate in the form of insoluble crystals when ingested.

All parts of this plant are dangerous to dogs. If your dog has eaten it, the symptoms to look out for are excessive drooling, pawing the mouth, swelling of the lips, mouth, tongue, or throat, and retching.

A severe reaction, if left untreated, can result in convulsions, renal failure, and coma. If you decide to keep a Philodendron in your home, make sure it is out of your fur babies’ reach.

philodendron in pot with grey background

Oleander Is One of the Most Poisonous Plants for Dogs

A common landscaping plant worldwide is invasive as the wind disperses its abundant seeds. Because of its size, the Nerium Oleander reaches (12 feet = 3.6m), making it an ideal shady spot for a dog to sit on a hot day. If your neighbors have Oleanders in their gardens or are used on the roadside, beware that they can spread to your garden if not controlled.

The Oleander is a low-maintenance plant that produces beautiful clusters of flowers in various colors. However but dog owners should be mindful that all parts of these plants are toxic to their pets. 

Some symptoms you will see if your dog has taken a snack on some Oleanders are upset stomach, Drooling, Diarrhea, difficulty breathing, change in heart rate or rhythm, and even death. Contact with the Oleander can cause skin irritation too, so they should be avoided if possible.

I worked for a Landscape nursery where we grew a large stock of Oleanders because they were featured in a garden magazine, only to find out later on that no one wanted to buy them because of their toxic properties. We sadly demolished hundreds of plants the following year as their popularity decreased rapidly.

oleander bush with pink flowers in the sun

Don’t Use Japanese Yew as a Christmas Tree

Commonly known as Buddhist pine or Southern yew, as an evergreen, these are often planted as hedges. Because of their pointy needle-shaped leaves and tolerance to pruning, they are favored as a realistic option for a Christmas tree. They produce small red berries that are not toxic to dogs, but the leaves, seeds, and bark are.

The leaves of the Japanese yew contain alkaloids Taxine A and B and are not only fatal to dogs but also cats, horses, and humans too.

Early symptoms of pet poisoning from Japanese yew will be seen as seizures and muscle tremors followed later by vomiting, lethargy, wobbly gait, cardiac failure, and low blood pressure, proven to be life-threatening.

japanese yew outside with dark background

Lily of the Valley Is One of the Most Toxic 

This one is native to the cool temperature of the northern hemisphere in Asia and Europe. Lily of the Valley is a common landscaping plant and famous for its fragrant bell-shaped blooms and ability to thrive in shady areas.

The cuteness of this plant is somewhat misleading, as even the most minor exposure can cause heart problems in a dog. The Lily of the valley (not regarded as a true Lily) contains cardio glycosides, which cause gastrointestinal upset. If the dog eats this Lilly’s flower, root, or leaves, it will induce vomiting, diarrhea, seizures, and even death.

While most lilies are known to be more poisonous to cats than dogs, other Lilly varieties can also be more harmful to dogs, such as Calla Lily, Asiatic Lily, and Peace Lily.

close up of white flowers lily of the valley

Autumn Crocus Disguised As an Innocent Flower

The Autumn crocus displays no leaves until the spring. So during Autumn and winter, you will see the light purple dainty-looking flowers emerge randomly from the ground alone. These innocent-looking flowers are also known as Naked ladies and are highly toxic to dogs.

All parts of the plant are toxic, not just the pretty flowers you see at the start of autumn. Therefore beware when these start to bloom, as even a small exposure can cause harm.

The Autumn crocus contains a poison called colchicine, which has no known anecdote. Symptoms that your dog ate the Autumn crocus will be seen with vomiting and diarrhea followed by gastrointestinal upset, liver damage, and if left untreated, can cause death.

purple flowers autumn crocus

Indoors or Outdoors, Cyclamen Can Cause Ill Effects

Popular indoor and outdoor plants grown for their long-lasting vibrant blooms during winter, the Cyclamen can make a bright statement in your plant collection. Unfortunately, Cyclamen contains terpenoid saponins, a toxic compound in the plant.

All parts of the plant are toxic if ingested, but the tubers, in particular, can cause the worst effects. The dog will need to dig up the plant’s root system to eat this part. Nevertheless if you are a dog parent, you will know that any behavior in fact can be possible!

If you are worried your dog has got hold of a Cyclamen, symptoms are excessive drooling, intense vomiting, diarrhea, and reduced heartbeat. If the dog is suffering from seizures, abnormal heartbeat, or even death, this can result from large amounts of tuber consumption.

pink and red cyclamen outside

Sago Palm Is Famous Among the Pet Poison Helpline

These expensive sought-after plants are often used as poolside plants or as eye-catching features in the home or garden. They look like small palms, are hardy evergreens, and like to grow in a warm tropical-like environment.

The entire plant contains Cycasin, beta-methylamino-L-alanine, and an unidentified toxin.3-6. These toxins irritate the gastrointestinal tract and cause vomiting, diarrhea, and depression.

If your dog is left untreated and has consumed the Sago palm, you will run the risk of your dog suffering from seizures, liver failure, ataxia, and other neurological damage.

The Sago plant can poison dogs in the most common way – when the dog eats the seed. The seeds are small enough for them to eat and more accessible than the prickly leaves of the palm itself.

close up of sago palm

Keep Dieffenbachia Out of Reach

Widely known as the Dumb cane, the dieffenbachia is a popular houseplant with lush mottled green and white leaves. The dieffenbachia belongs to the Araceae family, which contains calcium oxalate crystals and needle-like enzymes that are proven toxic to dogs and cats. Fortunately, dieffenbachia is not one of the most poisonous plants for dogs. But you should keep it with caution.

Still, if the stalk, roots, or leaves are ingested, the dog will show signs of burning or swelling of the mouth, difficulty swallowing, vomiting, and excessive drooling.

This is one of my favorite indoor plants because of its variegated foliage. When keeping it in my home, I make sure to keep it on a bookshelf or somewhere high where my four-legged friends can’t access it.

ariel view of dieffenbachia on white background

Rhododendron or Azalea Contains Neurotoxins

This pretty flowering shrub is used by landscapers worldwide; its low maintenance and vibrant blooms bring color to any space. Widely known as Azalea, the evergreen shrub contains a neurotoxin known as grayanotoxins. These are responsible for the poisonous effects on your dog.

Signs that your dog has been munching on your Azaleas are weakness, tremors, low blood pressure, and irregular heart rhythm. Rhododendron leaves are the most poisonous part of the plant. But they have many hidden poisons within their nectar, and the plant produces its chemicals to defend against insects.

According to the ASPCA | American Society for the Prevention of Cruelty to Animals, Rhododendrons are toxic to dogs, cats, and horses.

Tulips Can Cause More Harm Than Good

Many people love having Tulips in their homes or gardens as they symbolize springtime. To be honest, they look good enough to eat! Nevertheless if you are keeping Tulips in your home or garden, please beware; these are toxic to dogs, cats, horses, and humans.

Most toxins are in the tulip bulb. However the entire plant is generally dangerous if the dog ingests it. The toxins in tulips are called cardiac glycosides, affecting the protein synthesis in your dog’s cells if it eats one.

Small dogs and puppies are likely to suffer more if they consume tulips. Some signs to watch out for are vomiting, diarrhea, excessive drooling from the dog’s mouth, abdominal pain, mouth and esophagus irritation, heavy breathing, and a slow heart rate.

mulitcolored tulips outside

FAQ About What Plants Are Poisonous to Dogs

What should you not plant around your dog?

You should not plant toxic plants such as Cyclamen, Rhododendron, Oleander, Tulip, Japanese yew, Dieffenbachia, Sago palm, Autumn crocus, lily of the valley, cannabis Sativa, tomato, silver dollar, English ivy, English holly, American holly, Jerusalem cherry, devil’s ivy, Japanese rubber plant, corn plant around your dog. 

Will dogs stay away from toxic plants?

Dogs will stay away from a toxic plant, but their behavior can sometimes be unpredictable. Boredom or curiosity can spark them to take a nibble, and often we won’t find out until it’s too late. Try to stick with non-toxic plants in your home or garden just to be safe.

What is poisonous to dogs in the garden?

Along with the plants mentioned above, other things in your garden can cause harm to your dog. Mushrooms/ fungi, fallen grapes from the vine, Acorns, conkers, compost, and mulch made from cocoa husk can also cause problems to your dog’s stomach.

What plants are poisonous to dogs by touch?

Acacia shrubs, Mulberry trees, Oak trees, evening and garden primrose, Daylilies, Oleander, Sago Palm, Bottlebrush, and Bermuda grass are all outdoor plants that can harm your dog by touch. Spiderwort, Begonia, Philodendron, Aloe, Eucalyptus, Dieffenbachia, Cyclamen, and Philodendron are all indoor plants that can irritate your dogs’ skin.

Select Nontoxic Plants for Your Home for Peace of Mind

Dogs sniff around plants, which is one of their most common habits. Whether you have a few plants around your home or enjoy walking your dog in the local park, it’s essential to be aware of the poisonous plants that can cause harm to your furry friend.

Although this is not a complete list of the toxic plants to dogs- they are the most common and dangerous ones. Selecting nontoxic plant varieties for your home or garden will create a safe environment for your canine companion.

Contact your local veterinarian to provide treatment if you notice any symptoms. Toxic plants can have life-threatening effects, and as a pet owner, you must not hesitate.

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Alex Tinsman
An avid plant and flower lover! Ever since he was little, plants, flowers, and shrubbery of all kinds filled his life. Alex credits this fascination with nature's beauty to his mother and grandmother who were - and still are - dedicated gardeners. It's now Alex's mission to pass that same love for plants onto others and show them it's as easy as pie to bring nature inside.

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