Introduction to Poisonous Plants

Because some plants are edible and others are better left as ornamentals (or even as weeds!), every once in awhile, someone will make a mistake and eat some of a plant that is best not eaten. This can be especially problematic with children, who need to learn not to eat anything that hasn’t been served to them by a trusted adult. Keeping pets from eating poisonous plants that aren’t healthy for them is another consideration.

Some of the reasons poisonous plants pose problems:
  • Many poisonous plants look like edible plants.

    There are many stories, and even murder mysteries, about poison mushrooms that look very like edible mushrooms and fool even long-time gatherers.

  • A portion of the plant is edible, while other portions are poisonous.

    Rhubarb is a notable example—the leaves contain oxalates and raw or cooked leaves are poisonous.

    Elderberry is another: while cooked elderberries are used in pie, jam, and wine, fresh leaves, flowers, bark, buds, and roots can be toxic.

  • The poisonous plant is in the same family as edible plants.

    The nightshade family has poisonous members that produce toxic alkaloids, but in the same family are tomatoes, potatoes, paprika, green peppers, red peppers, and chilies. It is also worth noting specifically that tomato leaves and potato sprouts are both poison.

  • They look like they belong in a bouquet.

    Picking plants bare-handed is sometimes not a good idea. Garden gloves will protect you from leaves, stems, and sap that can hurt or irritate your skin, as is the case for buttercups and chrysanthemums.

  • They have similar or identical common names.

    Chokecherry and Jerusalem Cherry sound like types of cherries, but they are actually poisonous plants. Rosary Pea and Sweet Pea sound like types of edible peas, but they, too, are poisonous.

    Some plants have unusual effects. Dieffenbachia, called “dumb cane,” received it’s common name for a reason: the sap, which is toxic in open cuts, when ingested causes swelling of the tongue, throat, and larynx, and inability to speak.

Many other common plants are poisonous. Here is a list of some common ones.

Garden plants
  • Daffodils
  • Delphinium
  • Foxgloves
  • Hydrangea
  • Iris
  • Jack-in-the-Pulpit
  • Larkspur
  • Lily of the Valley
  • Morning Glory
  • Rhododendron
  • Oleander
  • Wisteria

House plants
  • Caladium
  • Elephant Ear
  • English Ivy
  • Hyacinth
  • Philodendron

  • Jimsonweed
  • Poison Hemlock
  • Privet
  • Yew

Around the holidays, it is important to keep in mind that both Holly and American and European Mistletoe are poisonous.

For further information on contact or ingestion of poisonous plants, contact Poison Control (800) 222-1222.

Written by Mary Elizabeth

Related Home Institute Articles

  • Plants for the Bathroom
  • Childproofing the Outside
  • Childproofing the Living Room
  • Babysitter Instructions II
  • Introduction to Poinsettias
  • Emergency Information
  • Introduction to Poison Control
  • Childproofing the Home Office