Poisonous Plant Facts


Let’s know about poisonous plants. Plants play a very important role in nature. They are everywhere in the world and make our land greener.

The most important job is that plants release oxygen into the air so we can breathe. Plants provide us with food, shelter, clothing, medicines and much more that we use in our daily lives.

But not all plants are good for us. There are many species of plants that carry poison. These poisons can cause itching, vomiting, abdominal pain, diarrhea, and even death. 

✍ Why are some plants poisonous?

In the wild, animals have ways to defend themselves against predators, or enemies who might want to eat them for lunch!

Plants cannot defend themselves as easily because they cannot move. Some plants have thorns, spikes or other outward ways to ward off predators. However, many plants use the internal, or inside, defense of poison.

The main reason for transporting the poison is protection against herbivores. Herbivores eat plants to survive, like rabbits, deers, etc.

You must have seen some plants which have thorns, spikes. Actually they protect themselves by their enemies (part of adaptations). However, many plants use internal or internal poison defense.

✍ Name of the most poisonous plants in the world.

1. Aconitum Napellus


According to the BBC report, in 2014, a gardener mysteriously died due to this plant.  The plant is also known by other more sinister names; wolf’s bane, Devil’s helmet and the Queen of Poisons.

Aconitum is one of the most deadly plants in the world. It is also known by the name of “the Queen of Poisons”, “wolf’s bane”, and “Devil’s helmet”. – Source

The roots and leaves are the most poisonous part of this plant. Symptoms of poisoning are tingling and numbness (after touching), vomiting and diarrhea if it has been eaten.

2. Castor oil plant


This plant is listed by the Guinness Book of World Records as the most poisonous plant on Earth. The seed of Castor Oil plants has an incredibly toxic chemical called ricin.

Eating this seed can lead to burning sensations in the mouth and throat, intense abdominal pain, vomiting, bloody diarrhea, increased heart rate, low blood pressure, and even death in a few days (if the victim left untreated).

3. Oleander (aka Nerium oleander)


Oleander is one of the most poisonous plants. Every part of this plant is full of toxic chemicals known as cardiac glycosides.

It can cause cardiac arrest if ingested unsystematically. Despite its deadly nature, it is planted for decorative purposes.

4. Hemlock Plant

Native to North America, this plant contains coniine, causes paralysis in the body’s neuromuscular joints if ingested.

Paralysis usually begins in a person’s legs and ascends through the body until it reaches the respiratory muscles, resulting in death.

It is also known as “the most violently toxic plant in North America”.

5. Rosary Pea Plant


The colorful seed contains the deadly poison abrin. It can cause difficulty breathing, fever, nausea, and fluid in the lungs.

The seeds are completely safe until they are scratched or the outer coating is damaged.
Apart from these, there are few more names of poisonous plants from which we need to be aware of.

6. Manchineel Tree

Manchineel Tree – commonly known as “apple of death” causes strong skin irritant.

manchineel _tree

7. Belladonna Plant


Belladonna is also called deadly nightshade, attacks the nervous system, rendering the nerve endings in involuntary muscle paralysis.


If you think your pet may have ingested a poisonous substance, immediately contact your local veterinarian or the ASPCA 24-hour emergency poison hotline directly at


8. English Yew


English Yew – Symptoms including dizziness, dry mouth, pupil weakness, weakness, uncontrolled heartbeat and possibly death.

9. White Snakeroot


White Snakeroot – Causes vomiting, thirst, delirium and ultimately, death.

It is widely believed that this poisonous plant was responsible for the death of Abraham Lincoln’s mother by drinking the milk of a cow that had eaten snakeroot plant.

✍ Most Common Poisonous Plants For Cats

  1. Marijuana
  2. Amaryllis
  3. Kalanchoe
  4. Oleander
  5. Cyclamen
  6. Sago Palm
  7. Azalea and Rhododendron
  8. Yew
  9. English Ivy
  10. Schefflera
  11. Daffodils
  12. Autumn Crocus
  13. Dieffenbachia
  14. Lily
  15. Tulip
  16. Castor Bean
  17. Hyacinth
  18. Chrysanthemum

✍ Most Common Poisonous Plants For Dogs

  1. Azalea and Rhododendron
  2. Sago Palm
  3. Tulips
  4. Oleander
  5. Lily of the Valley
  6. Chrysanthemum
  7. Foxglove
  8. Peony
  9. Milkweed
  10. Black Walnut
  11. Philodendrons
  12. Hydrangea
  13. Castor Bean
  14. Ivy
  15. Japanese Yew
  16. Amaryllis
  17. Gladiola
  18. Holly(American)
  19. Tomato Plant
  20. Aloe Vera
  21. Baby’s Breath

Complete List of Extremely Poisonous Plants for Dogs

✍ Most common poisonous plants to animals

Autumn Crocus






Castor Bean








Lily of the Valley

Sago Palm

English Ivy



Now its your turn – PLANT QUIZ

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