9 Common Poisonous Plants You May Grow

Poisonous plants – can you tell me which ones are?” That is a question I get all the . Very often the email is asking for a list of poisonous plants for cats.
Most of the time our focus is on plants to provide color where it looks best – indoors or in the . When we buy, plant or grow a plant we seldom think of the plant being some type of possible health hazard – beauty, color, form, function are what our focus is on.
I remember as a kid always being told never to eat the “rosary or castor plant – they are poisonous and can kill you”!
As adventurous as I was, the “peas and beans” were never tested.
The unfortunate side is that many plants you find in the garden and indoors may be poisonous – not the whole plant but parts of it in certain stages. Poisonous can be considered from fatal (death) to vomiting or mild upset stomach. Pets, children and even adults can all be at risk. Read on to learn more about these poisonous plants you grow.

9 Common Poisonous Plants

Here are 9 plants (there are many more) you are probably familiar with and carry some sort of “” label.
Now please do not assume that because these toxic plants are listed, doesn’t mean you should not grow them – just be aware. Let’s be realistic – there are many poisonous items in our home we use everyday… bleach maybe?

  • Hyacinth, , Daffodil – The flowers and bulbs are the toxic part and have been know to cause nausea, vomiting and diarrhea, which can be fatal.
  • Rosary Pea, Castor Bean – The of rosary pea and castor bean or castor oil plants are what to watch out for on these plants. The results can be fatal. It’s been noted that one single Rosary Pea has caused death. For adults just one or two Castor Bean seeds are close to a lethal dose.
  • Autumn Crocus & Star of Bethlehem – Again the bulbs are considered the toxic part which can cause nervous excitement and vomiting when ingested.
  • Iris – Underground stems considered highly toxic, severe upset digestive system but not usually that serious.
  • Oleander – The branches and leaves of this poisonous are extremely toxic. Has death, severe upset digestive system and affects the heart.
  • Wisteria – The toxic part is the seeds and pods. Many children have experienced the “poison” with a mild to severe upset digestive system.
  • Lantana Plant – Toxic, the green berries. Found growing “wild” in the southern United States, as a landscape ground cover or potted plant. The results can be fatal, affecting kidneys, lungs, nervous system and heart.
  • Jack-in-the-Pulpit – All parts of the plant but especially roots are toxic. Very much like the “Dumb Cane Plant” (Dieffenbachia) which causes burning and irritation of the mouth and tongue from the small calcium oxalate needle-like crystals contained in the plant.
  • Poison Oak – The acorns and foliage are known to be toxic especially when eaten. The symptoms slowly appear over days or weeks and can gradually affect the kidneys. However, it takes a large quantity amount for poisoning.

Also remember that some people may have reactions to plants and others will not. Plus humans are different than cats and . Animals have their own tolerance for and to plants.
Always treat unknown plants with respect, and make sure you teach your children to treat unknown plants the same.
What plants do you grow that are poisonous?
Source: AgriLife Extension

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