Looks can be very deceiving when it comes to flowers. So, today we will offer you a list consisting of 21 gorgeous but deadly flowers and poisonous plants as well as a quick summary and pictures of some of the deadliest plants in the world.

However, just like us, plants have been evolving for hundreds of thousands of years and have developed different self-preservation measures to protect themselves. Despite having predators, they have flourished by developing thorns, spines, and even deadly chemicals.

In this article, we’ll discuss 21 deadly flowers and lethal plants to watch out for. These dangerous flowers look harmless to the naked eye, but also contain toxins and poisonous substances that can be lethal for both humans and pets. Moreover, since we are in the fun section of this website, we will also present you with some of the deadliest plants and most poisonous species of vegetation that Mother Nature created for our amazement (and dismay.) Without any further introductions, let’s begin our “deadly journey”.

What do we hope that you learn from this article? Don’t go around eating flowers and plants if you’re not 110% sure they are safe to consume. Be especially careful if you have children and pets in the presence of these plants. It doesn’t take much for some of these flowers, plants, and roots to kill someone.

*Note: if you feel like you are having allergic reactions to a plant or flower please contact your physician or even 911. This article is intended to be used for educational purposes only, and does not include any treatments or treatment advice.

Our List of Beautiful But Deadly Flowers

1. Aconitum – The Queen of Poisons

The Queen of Poisons, Aconitum  - Deadly Flower

The first entry on our list of deadly flowers is Aconitum, also known as wolfsbane. It may belong to the buttercup family but there is nothing sweet or nice about it (except for its beauty.) A few drops of juice from this deadly flower’s roots and you may have some heart failure and cardiac muscles’ paralysis to deal with. It can also cause numbness and tingling. In other words, stay away from this plant!

Bi-color Aconitum  - Deadly Flower

How many people have died from Aconitum? Many, hundreds, if not thousands. It can be lethal with as little as 1 gram of plant consumption!

Other names

Other Names

Aconite, Monkshood, Wolf's-Bane, Leopard's Bane, Devil's Helmet

Botanical Nomenclature (Scientific Name)

Family: Ranunculaceae, Genus: Aconitum
Native to

Native Growing Area

Mountainous parts of the Northern Hemisphere
Toxicity

Degree of Toxicity

Deadly. It contains aconitine, a potent neurotoxin, mostly in its roots and tubers.

2. Oleander – The Fragrant Killer

The Fragrant Killer, Oleander - Deadly Flower

Oleander, known since Ancient Greece and Rome and described by Plinius, is one of the most toxic and deadly garden plants in the world. You may think about using it as an ornamental shrub or hedge, but keep in mind that the whole plant is poisonous. If you or your pet eat any part of an oleander plant, the poisoning symptoms can range from vomiting and diarrhea to seizures, coma, and possibly even death. Also, make sure you don’t even touch it, as some people suffer severe skin reactions upon contact.

How many people have died from Oleander? It is estimated that less than 100 adults have perished from oleander poisoning, but more toddlers and young children. It can be fatal with as little as 15 grams of oleander root or 8 seeds of the flower.

Other names

Other Names

Nerium, Nerium Oleander

Botanical Nomenclature (Scientific Name)

Family: Apocynaceae, Genus: Nerium
Native to

Native Growing Area

Mediterranean region. Grown as ornamental plants worldwide.
Toxicity

Degree of Toxicity

Deadly. Ever part of this plant contains the cardiac glycosides oleandrin and oleandrigenin.

3. Lily of the Valley – The Innocent Killer

The Innocent Killer, Lily of the Valley - Deadly Flower

The Lily of the Valley smells terrific but if you accidentally  ingest this flower, expect the worst. Lily of the Valley is a “grade 1” deadly flower on the poison scale. Also, it has cardiac glycosides, which are a class of substances that inhibit the Na+ K+ ATPase enzyme. This increases the force of heart contractions which create a similar effect as the digitalis effect, meaning that this delicate, gorgeous, tantalizing flower is also one of the deadliest killer plants in existence.

How many people have died from Lily of the Valley? We couldn’t find any recorded human deaths of this flowering plant despite the high concentrations of toxins found therein. It is said that it can be fatal to consume as few as two leaves for young children and pets or as little as 0.2% of a mammal’s bodyweight.

Other names

Other Names:

Convallaria majalis, May bells, Our Lady's tears, and Mary's tears

Botanical Nomenclature (Scientific Name)

Family: Asparagaceae, Genus: Convallaria
Native to

Native Growing Area

Asia and Europe
Toxicity

Degree of Toxicity

Deadly. The whole plant is highly poisonous and contain saponins and Aze, a poisonous animo acid.

4. Brugmansia – The Angel’s Trumpet

The Angel’s Trumpet, Brugmansia - Deadly Flowers

One of the most toxic ornamental plants out there, Brugmansia contains alkaloids that you do not want to ingest or touch. Interestingly enough, the toxins of this plant – scopolamine, atropine, and hyoscyamine – are used in medicine and pharmacology, however the use of any part of this plant can be deadly without  doctor supervision. We strongly suggest that you keep your distance!

How many people have died from Brugmansia? At least 45 fatalities have been reported from Brugmansia and Datura poisoning since 1983. It can kill people with as little as 10 milligrams of brugmansia, which equates to as few as 10 flowers.

Other names

Other Names:

Brugmansia ‘Feingold’

Botanical Nomenclature (Scientific Name)

Family: Solanaceae, Genus: Brugmansia
Native to

Native Growing Area

Tropical parts of South America, Andes, Venezuela, Chile, south-eastern Brazil. Grown as ornamental plants worldwide.
Toxicity

Degree of Toxicity

Deadly. Every part of this plant is highly poisonous and contains tropane alkaloids, including hyoscine (scopolamine), hyoscyamine, norhyoscine.

5. Azaleas – The Mind-Altering Honey

The Mind-Altering Honey, Azaleas - Deadly Flowers

All parts of azaleas are poisonous for humans and animals. While azaleas are gorgeous to look at, they are deadly flowers containing grayanotoxins. Consuming a small amount of this plant may not likely lead to severe illness, but consuming a large amount of the plant can lead to life-threatening conditions.

How many people have died from eating azaleas? It is estimated that very few adults have died from azalea poisoning, but more children, animals, and reptiles. It can be fatal with as little as 100 grams of azalea leaves for children.

Other names

Other Names:

Rhododendron (every azalea is a rhododendron but not all rhododendrons are azaleas.)

Botanical Nomenclature (Scientific Name)

Family: Ericaceae, Genus: Rhododendron
Native to

Native Growing Area

Asia, Europe, and North America. Grown as ornamental plants worldwide.
Toxicity

Degree of Toxicity

Deadly. They contain andromedotoxins in their leaves and nectar. Their nectar can be used by bees to create lethal honey, known as ‘mad honey’!

6. Checkered Lily – The Lazarus Bell

The Lazarus Bell, Checkered Lily - Deadly Flower

You may have heard about this flower as a snake’s head fritillary. As the title suggests, this plant is poisonous like a venomous snake. Like the lily of the valley, the checkered lily is a grade-1 poisonous plant that you should handle with a lot of care. Seriousness aside, it somewhat reminds us of the piranha plants in Super Mario Bro’s.

How many people have died from eating checkered lily? We could not find any recorded deaths from checkered lily consumption in our research but it doesn’t take much for it to be toxic for cats. Felines that have consumed as little as two leaves of this lily can die in as little as 3 days.

Other names

Other Names:

Snake's head, Chess flower, Frog-cup, Leper lily, Drooping tulip, Fritillary

Botanical Nomenclature (Scientific Name)

Family: Liliaceae, Genus: Fritillaria
Native to

Native Growing Area

Europe and western Asia
Toxicity

Degree of Toxicity

Deadly. Its bulbs contain poisonous alkaloids.

7. Belladonna – The Deadly Nightshade

The Deadly Nightshade, Belladonna- Deadly Flowers

This perennial herbaceous plant in the nightshade family Solanaceae is as deadly as its reputation. You’ve probably read crime novels or seen CSI TV shows related to belladonna poisoning. According to the USDA Forest Service, belladonna means “beautiful woman” in Italian but is still a very poisonous flower!

With all these highly toxic compounds, one might wonder why deadly nightshade was and is still being used by people. As with many poisonous plants there are many reasons for their use, both good (medicinal) and bad (weapons and poisons). The Romans used belladonna as a biological weapon to contaminate their enemies’ food reserves. In Shakespeare’s play, Macbeth, the Scottish army defeats the Danes by contaminating their liquor supply with belladonna, inducing a deep, comatose sleep, and murdering them in their hapless state. Deadly nightshade was also an important plant in the medieval witches’ pharmacopoeia in brews and salves, used as a constituent in their flying ointments. During World War II, the Germans invented a deadly, odorless nerve gas and the only antidote to its paralyzing effects turned out to be atropine(found in belladonna.)

How many people have died from consuming belladonna? It is unknown but is much more dangerous for children since they’re smaller. There are many stories, perhaps fables of people using it throughout written history to poison their enemies. It is said that as few as ten berries ingested can be lethal to an adult.

Other names

Other Names:

Atropa Belladonna

Botanical Nomenclature (Scientific Name)

Family: Solanaceae, Genus: Atropa
Native to

Native Growing Area

Europe, North Africa, and Western Asia
Toxicity

Degree of Toxicity

Deadly. One of the most toxic plants. The entire plant contains tropane alkaloids.

8. Jessamine – The Twining Vine

The Twining Vine, Jessamine - Deadly Flowers

Carolina jessamine is a common garden plant loved for the profusion of yellow flowers it yields in the summer. However, it is also one of the deadliest flowers out there. It contains neurotoxic alkaloids that affect nerve endings and can cause paralysis, muscle weakness, and clonic convulsions and seizures in all mammals (both animals and humans.) Also, the whole plant is poisonous, but you have to watch out for the flowers and roots with even more care as they are the most dangerous.

How many people have died from jessamine? There are several cases of adults and children passing away from intentional (suicide) or accidental consumption. Just ingesting one flower can be enough to be lethal to children and pets.

Other names

Other Names:

Gelsemium sempervirens, Yellow Jessamine, Carolina Jessamine, False Jasmine, Evening Trumpet Flower, Gelsemium, and Woodbine.

Botanical Nomenclature (Scientific Name)

Family: Gelsemiaceae, Genus: Gelsemium Juss
Native to

Native Growing Area

Subtropical and tropical America and southeastern and south-central United States
Toxicity

Degree of Toxicity

All its parts contain the toxic alkaloids gelsemine and gelseminine and its sap can cause skin irritation.

9. Poison Hemlock – The Philosopher’s Bane

The Philosopher's Bane, Hemlock - Deadly Flowers

Poison hemlock (Conium maculatum) is one of the most poisonous and deadliest plants in the world. However, you should know the difference between poisonous hemlock and Queen Anne’s lace (Daucus carota). Poisonous hemlock grows throughout the United States. It is toxic to pets, livestock, and humans, so make sure you keep an eye on it should you choose to grow it in the garden.

Even though both are in the Apiaceae family and have hollow stems, poison hemlock’s stem is hairless and has purple blotches. Also, even a very young poison hemlock will display the purple blotching. On the other hand, the stem of Queen Anne’s lace doesn’t have purple blotches and is hairy. See the photos below for a comparison.

How many people have died from poison hemlock? There are several reported deaths from poisonous hemlock. According to a CDC report on hemlock poisoning it is reported that at least 63 people have died between the years 1979 through 1992 from accidental consumption. It can be fatal with as little as 150 milligrams eaten.

Other names

Other Names:

Conium Maculatum, Poison Hemlock

Botanical Nomenclature (Scientific Name)

Family: Apiaceae, Genus: Conium Maculatum
Native to

Native Growing Area

Europe and North Africa
Toxicity

Degree of Toxicity

Deadly. This is the lethal plant that killed Socrates. It contains conium and multiple toxic alkaloids.

10. Ornithogalum – The Star of Bethlehem

The Star of Bethlehem, Ornithogalum - Deadly FlowersEvery bit of this cool-season perennial of the Lily family is poisonous. Make sure you stay away from its bulbs and roots as they are the most dangerous and poisonous. This deadly flower – that blooms in late spring or early summer – contains cardiac glycosides that have life-threatening side effects. Also, you should never use it as medicine.

It’s important to know what it looks like. Its flowers are showy white with six petals on each. The petals have a noticeable greenish stripe down the middle on the back. Please keep your dogs and other animals away from it, as it can really harm them too!

How many people have died from ornithogalum? We couldn’t find any reported human deaths but deaths in canines has happened. It has also caused blindness in cattle. This flower can kill a horse (and likely an adult human) by eating as few as eight flowers.

Other names

Other Names:

Ornithogalum Umbellatum

Botanical Nomenclature (Scientific Name)

Family: Asparagaceae, Genus: Ornithogalum
Native to

Native Growing Area

Europe and Southern Africa
Toxicity

Degree of Toxicity

Some of the deadly plants from this genus contain alkaloids and cardenolides in their bulbs.

11 More Deadly and Killer Flowers You Should Also Know About

As we said earlier, here we will resume with 11 more poisonous flowers you should know about before planning your garden.  Planting these flowers and ornamentals in your home or garden could be disastrous! With that being said, let’s learn a little about these 11 other deadly flowers!

  1. Castor Oil Plant – Nausea, bloody diarrhea, blood pressure drops, and intense abdominal pain are some of the symptoms of ricin poisoning, which in high enough doses, can trigger death. Also, according to the Guinness Book of World Records, 2007, the castor plant is the most poisonous plant in the world.
  2. English Ivy – This beautiful indoor plant cleans the air and makes an excellent hanging vegetal ornament, but keep in mind it is toxic to pets and children.
  3. Dracula’s Flower (Dracunculus vulgaris) – hard to ingest, as when in bloom, its flowers reek of rotten meat. The face of some of these flowers resemble a monkey.
  4. Titan Arum – Also known as the corpse flower  for its rotting-meat smell.
  5. Gypsophila – Also known as baby breath, looks wonderful but can cause skin irritation, vomiting, nausea.
  6. Bleeding Heart – A gorgeous plant with flowers shaped like hearts that appear to be dripping blood. The whole plant is poisonous.
  7. Bloodroot – Beautiful, but leading to organ failure if ingested.
  8. Foxglove – Contains digitalis, fatal.
  9. Morning Glory and Sweet Peas – Smell it only, as it can lead to diarrhea, vomiting, or hallucinations.
  10. Peace Lily – One of the most beloved indoor plants that clean the air – just make sure it does not get in contact with children and pets.
  11. Irises (all types) – One of those toxic flowers that look gorgeous but can lead to vomiting, fever, or diarrhea for people and pets. Also, in the classic novels, ladies used this deadly flower to poison themselves.

Final Thoughts

What did you think about our list of the 10 most beautiful but lethal flowers and eleven more dangerous flowering plants you should stay away from? In the comments below tell us what you think about these powerful plants. Also, if you’d like us to add one or more dangerous and poisonous plants to the list, let us know in the comments section. We are also truly interested to find out if you had any experience with these twenty-one plant murderers. We do, however, hope you don’t have any experiences of this kind!

Be very careful around these plants, as they are dangerous for both humans and pets. If you happen to come into contact with these or others that give you a reaction please seek medical help immediately so that you don’t become the next statistic!

Denis Sgarbura - Retired Contributor
About the Author - Denis Sgarbura

Hello. I’m Denis. My passion for growing plants started when I was around 10 or 11 years old. My grandpa loved to take care of roses. He had a breathtaking rose garden. I wanted one badly. So, I started my own. I was stoked when my roses showed signs of growth. It became a competition: my garden vs. his garden. He won every time, but I never gave up and did my best to make it extraordinary. I read everything there was to know about roses and how to grow them.

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