The following plants have been identified as toxic. Depending on the plant, symptoms may be mild to severe, and for many of these, only certain parts of the plant are toxic. More detailed information is available from your regional Poison Control Center.
| Anemone | Holly Berries | Narcissus |
| Angel Trumpet Vine | Horestail Reed | Nightshade |
| Apricot (kernels) | Hyacinth | Oleander |
| Arrowhead | Hydrangea | Periwinkle |
| Avocado (leaves) | Iris | Peyote (mescal) |
| Azaleas | Ivy | Philodendron |
| Betel Nut Palm | Jack-in-the-Pulpit | Poison Hemlock |
| Bittersweet | Jequirity Bean or Pea | Poison Ivy |
| Buckeye | Jerusalem Cherry | Poison Oak |
| Buttercups | Jasmine (Jessamine) | Poppy |
| Caladium | Jimson Weed (Thorn Apple) | Pokeweed |
| Calla Lily | Jonquil | Potato (sprouts) |
| Castor Bean | Lantana Camara (Red Sage) | Primrose |
| Cherries (wild & cultivated) | Larkspur | Ranunculus |
| Crocus, Autumn | Laurels | Rhododendron |
| Daffodil | Lily-of-the-Valley | Rhubarb (blade) |
| Daphne | Lobelia | Rosary Pea |
| Delphinium | Marijuana | Star-of-Bethlehem |
| Devils Ivy | Mayapple | Sweet Pea |
| Dieffenbachia (Dumb Cane) | Mistletoe | Tobacco |
| Elderberry | Moonseed | Tomato (vines) |
| Elephant Ear | Monkshood | Tulip |
| English Ivy | Morning Glory | Water Hemlock |
| Four O'Clock | Mother-in-Law's Tongue (Snake Plant) | Wisteria |
| Foxglove | Mushroom | Yew |