Flower Facts Flower Information

Poisonous Flowers and Plants to Avoid

white and pink oleanders, one of the most poisonous flowers

WARNING: If you, your children, or pets have been exposed to any of the toxic plants listed below or any you believe are toxic, please contact the Poison Control Center hotline immediately at (800) 222-1222. They are available 24 hours a day, 7 days a week. If you think you are someone you know has come into contact with a poisonous plant, check with the hotline as soon as possible.

At The Bouqs Co., we believe that flowers express caring and help build emotional connections. Flowers contribute to how we commemorate special occasions and communicate without the need for words. Good intentions should always be met with clear & responsible actions. Our customers, our partners & our employees are all a part of our community. In our continued effort to keep our customers and readers informed, we want our community to be aware of which flowers and plants might be dangerous or toxic to people and our beloved pets.

Throughout history, plants and flowers have been famed not just for their fragrance and beauty but also for their potential dark side. Yes, that gorgeous bundle of blooms and greenery can also be highly toxic to humans and animals, causing skin irritation, illness, and even death. Understandably it’s a good idea to know what dangerous plants you need to stay away from.

We love talking about all things flora at The Bouqs. Just because a plant or flower might be toxic to eat, doesn’t mean you can’t enjoy the flower. It just means being extra aware and careful and keeping away from children and pets. Beyond this list, some people may have allergic reactions to flowers and plants not considered generally toxic. Make sure to ask about any allergies before sending a flower arrangement.

Plant Toxicity

Plants produce poisonous or toxic substances as a chemical defense mechanism against predators. Plant predators can include the herbivores that eat them. Think of how porcupines have spikes or skunks that release a strong malodor when under duress. Flower and plant poisons function the same way. It’s important to understand what symptoms you might notice if you accidentally ingest any toxic plants and what toxic properties that flowers and plants may carry.

When in doubt, don’t try to self-diagnose. Contact the poison hotline mentioned at the top of this article and give the professionals all the information.

Poisonous Plants

If you’re an avid gardener or lover of nature, coming across new and interesting plants is all part of the joy of nature. Unfortunately, while most are fun to inspect and investigate, and even eat in some cases, there are also many dangerous plants lurking in the undergrowth.

Deadly Nightshade

With such an ominous name it’s hardly a surprise that Deadly Nightshade isn’t exactly a nature lover’s best friend. The legend of Macbeth has it that his troops poisoned an invading Danish army with wine made from deadly nightshade berries. It’s not just bearded Vikings who’d be attracted to such a plant, either. With its bright black, plump berries, children and curious pets are especially at risk of being tempted to taste the fruit.

The stems, leaves, berries, and roots all contain atropine and scopolamine which cause paralysis of involuntary muscles (i.e., your heart.) It can also cause severe skin irritation just from coming in contact with its leaves.

Species Name: Atropa
Toxicity: Major
Toxic Agent: Atropine, scopolamine, hyoscyamine
Symptoms: Slurred speech, sensitivity to light, hallucinations and confusion, respiratory difficulty, rapid heart rate, dry mouth, slurred speech, dilated pupils, loss of balance, respiratory difficulty
Potential Cause of Death: Breakdown of the parasympathetic nervous system
Native to: Europe, North Africa, West Asia, and North America

Castor Bean Plant or Palm of Christ

Though castor oil has long been a multi-use ingredient in home remedies, the seeds themselves, before being processed, are major sources of the poison ricin. In fact, the plant’s Latin name ricinus communis is a bit of a giveaway. Native to an area from Africa to South Asia, it can nevertheless be found in many gardens around the world as an ornamental plant. As few as one or two poisonous seeds can be fatal for a child.

The plant has a distinctive spiky ball-like sed capsule and the seeds are large, oval, and contain a nub at one end.

Species Name: Ricinus
Toxicity: Major (beans)
Toxic Agent: Ricin
Symptoms: Bloody diarrhea, severe dehydration, decreased blood pressure, difficulty urinating, rapid heart rate, convulsions, nausea and vomiting, rapid heart rate
Potential Cause of Death: Circulatory shock
Native to: Mediterranean, East Africa, South Asia


Up to five million people die from tobacco-related diseases every year. This is generally because of the damage caused by smoking. Even in its non-flammable form, it is one of the most poisonous plants around. It contains nicotine (a common ingredient in most insecticides) and anabasine, which can be fatal if eaten in large amounts.

Species Name: Nicotiana tabacum
Toxicity: Minor (eating a few leaves), Major (smoking, chewing)
Toxic Agent: Nicotine, Anabasine
Symptoms: Vomiting, nausea, dizziness (plant)
Potential Cause of Death: Cancer from smoking processed tobacco
Native to: North and South America


The Christmas favorite for tipsy family members that weirdly look to steal kisses. But remember, mistletoe can ruin your holidays in more ways than one. This is because ingesting the berries, leaves, or shoots can cause severe abdominal pain and diarrhea. Extreme cases can even lead to death through cardiovascular collapse and they are also extremely toxic to cats and dogs.

Species Name: Santalales
Toxicity: Minor (small amounts), Major (large amounts)
Toxic Agent: Pharotoxin, viscotoxin
Symptoms: Blurry vision, fever, vomiting, diarrhea, drowsiness, slow heart rate, seizures
Potential Cause of Death: Can cause miscarriage
Native to: Europe and Britain, introduced to North America


The fictitious street of the Desperate Housewives was doomed to poisonous behavior right from the start. Wisteria trees, though beautiful when in bloom, also have highly toxic seeds. They are known to cause vomiting, diarrhea, abdominal pain, and depression of the central nervous system.

Wisteria plants have gorgeous hanging blossoms often in vibrant purple shades. Due to their beauty, they often serve as ornamental garden plants or even as bonsai.

Species Name: Wisteria sinensis
Toxicity: Minor
Toxic Agent: Lectin, wisterin
Symptoms: Burning sensation in the mouth, vomiting, diarrhea, abdominal pain,
Potential Cause of Death: Gastrointestinal hemorrhage in pets
Native to: Asia, North America

Water Hemlock

When something is described as “the most violently toxic plant in North America” you can probably guess it is something to steer clear of. This is the case with Water Hemlock which can sometimes be confused with edible stuff like celery and parsnips. Violent convulsions are just one of the effects of its poison (along with death) while survivors have been known to suffer amnesia and tremors for the rest of their lives. Be sure to examine any questionable plants carefully to make they aren’t the poison hemlock.

Species Name: Conium
Toxicity: Major
Toxic Agent: Cicutoxin
Symptoms: Vomiting, trembling, rapid respiration, convulsions, weakness, irregular heartbeat, hallucinations, numb skin or tingly skin, kidney failure, drooling
Potential Cause of Death: Respiratory failure
Native to: Mediterranean and Southern Europe

Strychnine Tree or Quaker Button or Poison Nut Tree

Quaker Button or Poison Nut Tree contains the toxin strychnos nux-vomica or strychnine. Native to India and south-East Asia, the poison comes from the seeds and dried blossoms. The toxin results in muscular convulsions and if enough is ingested, it can be fatal. It’s also highly toxic to dogs so if you think you’re pet ate some, look out for anxiety, drooling, high body temperature, seizures, and tremors or get them to a vet immediately.

Species Name: Strychnos nux-vomica
Toxicity: Major (seeds and bark)
Toxic Agent: Strychnine
Symptoms: Muscle pain, difficulty breathing, dark urine, rigid arms and legs, convulsions
Potential Cause of Death: Respiratory failure
Native to: Southeast Asia and India

Poisonous Flowers

It’s not just the thorns of a rose that give reason to be wary of flowers. Some of those pretty petals can also be quite poisonous too. Everything should be fine, though, as long as you keep yourself, kids, and pets away from the these poisonous flowers.


Blooming in pink, white, yellow, and red, oleanders are always pretty to have around the house. Watch out though, the entire plant is toxic from petals to roots. The oleander plant is a classic beauty with memorable flowers that attract many gardeners so make sure you’ve taken the proper safety precautions if you grow this plant in your garden.

Species Name: Nerium oleander
Toxicity: Major
Toxic Agent: Oleandrin and oleandrigenin
Symptoms: Vomiting, skin irritation, tremors, drooling, drowsiness, loss of appetite, seizures, death
Potential Cause of Death: Respiratory paralysis, Heart failure
Native to: Mediterranean, Southwest Asia

Lily of The Valley

The lily of the Valley has delicate, bell-shaped flowers that look attractive in many gardens or flower arrangements. It also exudes a sweet scent so be careful not to be lulled into complacency when growing this deadly flower. With toxic compounds, known as cardiac glycosides, ingesting Lily of the Valley can cause an abrupt trip to the hospital, with dizziness, vomiting, and rashes being common symptoms. These little bells are also highly toxic to animals, especially cats.

Species Name: Convallaria majalis
Toxicity: Major
Toxic Agent: Convallarin
Symptoms: Headache, abdominal pain, dizziness, rash, hives, blurred vision, excessive urination, lethargy, irregular heartbeat, seizures
Potential Cause of Death: Heart failure
Native to: Northern Asia and Europe


One of the most popular “true blue” flowers around, hydrangea bouquets have a bit of a nasty secret. Its flowers and leaves contain cyanogenic glycosides, basically the same as cyanide pills, which cause dizziness, convulsions, and fainting.

Species Name: Hydrangea macrophylla
Toxicity: Minor
Toxic Agent: Amygdalin
Symptoms: Diarrhea, vomiting, depression
Potential Cause of Death: usually non-lethal but be careful
Native to: Asia and Americas

Foxglove or Dead Man’s Bells

The dainty little foxglove is actually full of digital poison, i.e., digitalin, digitonin, and digitoxin. While these might sound like some new technology start-up, they are, in fact, highly toxic chemicals. They are especially dangerous for deer, as well as other animals, though children have died from ingesting them.

Species Name: Digitalis purpurea
Toxicity: Major
Toxic Agent: Digoxin
Symptoms: Blurry vision, vomiting, drooling, tremors, abdominal pain, hallucinations, severe headache, decreased heart rate, irregular heartbeat
Potential Cause of Death: Cardiac arrest
Native to: Southwest Europe, Northwest Africa, Central and Western Asia


A Christmas and holiday favorite, poinsettias are not in the edible flower category. While there have only ever been two cases of death caused by the poinsettia’s poisonous sap, they remain dangerous. Cats and dogs are especially vulnerable to this tropical garden favorite so take extra care of your furry friends around them.

Species Name: Euphorbia pulcherrima
Toxicity: Mild
Toxic Agent: Diterpenoid euphorbol
Symptoms:Vomitting, drooling, skin irritation, occasionally diarrhea
Potential Cause of Death: Almost never lethal
Native to: Mexico and Central America

Clematis or Leather Flower or Traveler’s Joy

Take care to wear gloves while pruning any clematis flowers in your garden or bouquet of cut flowers. They contain anemonin which affects both humans and animals. The effects can range from reasonably mild dermatitis and skin irritation to mouth ulcers to more serious nausea and drooling in dogs and horses.

Species Name: Clematis
Toxicity: Mild
Toxic Agent: Protoanemonin
Symptoms: Salviating, vomiting, diarrhea
Potential Cause of Death: Not lethal
Native to: North America

Angel’s Trumpet

The pretty bell-shaped flowers of the angel’s trumpet look delicate but that hides the fact they can be highly toxic. Ingesting these pretty flowers can cause anything from hallucinations to paralysis, memory loss, and even cardiac arrest. The leaves and the seeds contain the highest amount of poison.

Species Name: Brugmansia
Toxicity: Major
Toxic Agent: Scopolamine
Symptoms: Blurry vision, dry mouth, fever, amnesia, hallucinations, diarrhea, muscle weakness, paralysis, rapid heart rate
Potential Cause of Death: Cardiac arrest
Native to: South America


Larkspur or delphinium are popular ornamental plants but people should be careful. Larkspur is toxic not only to people, but to livestock as well. Larkspur is a common cause of cattle poisoning across many ranches especially in the western states and at higher elevation levels. Heifers are estimated to be three times more likely to become poisoned than bulls and steers. The method of posioning is called neuro-muscular paralysis which can lead to respiratory paralysis.

Species Name: Delphinium
Toxicity: Major
Toxic Agent: Methyllycaconitine
Symptoms: Rapid heart rate, digestive issues, skin irritation, abdominal pain, convulsions, respiratory problems
Potential Cause of Death: Respiratory paralysis
Native to: Mediterranean

Monksblood or Wolf’s Bane

Wolf’s Bane or Monksblood has purple flowers that pop with color. But, it’s one of the oldest poisons used by humans. The roots are the most toxic part of the plant. Wolf’s bane has been used by hunters and warriors on the tips of spears and arrows. The plant is also used in herbal preparations around the world which sometimes results in accidental poisonings.
Fun Fact: Wolf’s bane got its name because people believe the plant would ward off and repulse werewolves.

Species Name: Aconitum
Toxicity: Major
Toxic Agent: Aconitine
Symptoms: Vomiting, burning sensation in the abdomen, tingling feeling in the mouth, decreased blood pressure, motor skill weakness, decreased heart rate, irregular heartbeat, seizures,
Potential Cause of Death: Heart failure
Native to: Mountains in Western and Central Europe

Suicide Tree

Native to India and south-East Asia, this plant earned its infamous nickname because it’s said to be the most common method of suicide in many regions. Researchers estimated that it was responsible for up to 3,000 deaths per year. It’s also been hypothesized that it’s a common poison for homicides specifically because it’s hard to tease out which deaths are suicide and which are homicide.

Species Name: Cerbera odollam
Toxicity: Major
Toxic Agent: Cerberin
Symptoms: Vomiting, irregular heartbeat, increased heart rate, coma, drowsiness
Potential Cause of Death: Cardiac arrest
Native to: East Africa and South Asia


Bloodroot has a history befitting its name. These white and yellow flowers have historically been used for red dyes. On the heavier side, Native American tribes have used bloodroot to induce abortions in horses as well as humans. Interestingly, the Algonquin also used bloodroot for love charms, just don’t lick the charm.

Species Name: Sanguinaria
Toxicity: Major
Toxic Agent: Sanguinarine
Symptoms: Sedation, vomiting, decreased blood pressure, vertigo, shock, coma
Potential Cause of Death: Heart failure
Native to: North America around the Great Lakes


Henbane, also known as stinking nightshade, has been used since at least the time of Pliny the Elder who documented its use as a sedative and analgesic. It’s made appearances in herbalist remedies and also alongside deadly nightshade, datura, and mandrake in poisonous concoctions. It’s also been found near Viking graves which, along with its hallucinatory properties make historians suspect Viking berserkers used the plant to induce rage when they would go to war.

Species Name: Hyoscyamus niger
Toxicity: Major
Toxic Agent: Hyoscyamine
Symptoms: hallucinations, increased blood pressure, rapid heart rate, extreme fever
Potential Cause of Death: Heart failure
Native to: Eastern Europe and Asia

White Snakeroot

White snakeroot is toxic due to a poison called tremetol. It can be dangerous because livestock can consume the snakeroot which causes the milk and meat of the animal to become toxic with the poison. Tremetol is accumulative so it’s possible to ingest some toxic milk or meat and not experience the effects until the person reaches a threshold. The danger comes from continual ingestion of toxic meat/milk before symptoms make it known. Tremetol can cause muscular degeneration and affect the heart. Historically people called this type of poisoning “milk sickness.”

Species Name: Ageratine atlissima
Toxicity: Major
Toxic Agent: Tremetol
Symptoms: dehydration, exhaustion, severe vomiting, tremors, trembling
Potential Cause of Death: Dehydration
Native to: Eastern North America

Morning Glory

The good news is the actual morning glory blossoms are not poisonous. The bad news is the seeds are toxic with a chemical compound similar to LSD. Ingesting large amounts can cause hallucinations and other symptoms such as diarrhea or vomiting.

Species Name: Ipomoea muricata
Toxicity: Minor/Major (seeds)
Toxic Agent: Ergine
Symptoms: Severe hallucinations, vomiting, diarrhea, dizziness
Potential Cause of Death: Dangerous drug interactions
Native to: Central and South America

Safety First When Dealing with Unknown Flowers and Plants

Naturally, when bringing flowers into your home, you’re going to want to know which might potentially cause problems. If you’re looking for Halloween flowers for a gift or a party, choose them based on color and arrangement. It’s best to avoid the most toxic flowers and plants, even if some are remarkably beautiful.

Our artisanal florists are experts in the creation of handcrafted bouquets you can order online for delivery across the country. We label our bouquets for toxicity. If you have any questions, don’t hesitate to reach out to our customer support before ordering a bouquet you believe might be toxic.

Poisonous Flowers and Plants Infographic

infographic of the most poisonous flowers and plants

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