Gardening Plant Problems Weeds

22 Common Poisonous Plants

Illustration of types of poisonous plants to know

The Spruce/Catherine Song.

Identify what poisonous plants may be present in your backyard using these pictures of common toxic plants in North America. This list will help you to identify vegetation that can be dangerous if touched or consumed. The level of toxicity varies widely but care should be taken before planting or handling the following 22 examples.

Warning

Always use care and discretion when eradicating toxic plants; the safest option is to hire professionals rather than trying to do the work yourself.

  • 01 of 22

    Bittersweet Nightshade

    Colorful bittersweet nightshade berries.

    The Spruce / David Beaulieu

    Bittersweet nightshade (Solanum dulcamara) is a very common woody weed and is especially dangerous to have around kids because of the brightly colored berries. The highest level of toxicity for humans and animals comes if the berries are consumed but all parts of the plant (bark, leaves, sap) are toxic. The rapidly growing vine is often confused with American bittersweet and Oriental bittersweet plants.

  • 02 of 22

    Chinese Lanterns

    Chinese lantern pods in three colors.
    G.N. van der Zee/Getty Images

    Related to bittersweet nightshade, the Chinese lantern (Physalis alkekengi) plant's leaves and fruit are toxic. Commonly grown by crafts enthusiasts, the initial color of the fruit's husk is green. This color changes to yellow late in the summer and by fall, it is a rich orange. The colorful pods are used in dried floral arrangements and wreaths.

  • 03 of 22

    Foxglove

    foxglove

    The Spruce / Evgeniya Vlasova

    Foxgloves (Digitalis spp.) are tall, flowering biennials that grow well in a spot with dry shade. They bloom with multiple tubular, often freckled, flowers that form on a spike in colors ranging from purple to white. Resistant to deer and rabbits, if consumed by humans, their flowers, leaves, roots, and stems are among the most toxic specimens commonly grown on landscapes.

  • 04 of 22

    Mountain Laurel

    Minuet laurel has reddish-pink flowers.
    David Beaulieu

    If you live in the countryside in eastern North America, you may have some mountain laurel (Kalmia latifolia) growing wild in your backyard. Cultivars of mountain laurel are also sold at nurseries, including the beautiful 'Minuet' laurel. Mountain laurel, azaleas, and rhododendrons (Rhododendron spp.) belong to the heath family and the bark, sap, leaves, and flowers are toxic.

    Continue to 5 of 22 below
  • 05 of 22

    Castor Bean

    Castor bean plant

    Guenter Fischer/Getty Images

    Castor bean (Ricinus communis) is a tropical plant widely grown as an annual in northern climates, often as a potted plant for patios, decks, or porches. The leaves, stalk, and seed heads are all attractive. The laxative, castor oil, is derived from castor bean plants, but so is the deadly toxin, ricin.

  • 06 of 22

    Yew

    Yew shrub with berry.

    IMS68/Pixabay

    Yew (Taxus spp.) bushes can be grown in sun or shade. This plant's shade tolerance gives landscape designers an important option in challenging areas. But its fleshy, bright-red berries contain a toxic seed. The needle-like leaves are toxic to humans and animals.

  • 07 of 22

    Poison Sumac

    Fall foliage of poison sumac shrubs.

    The Spruce / David Beaulieu

    Both the leaves and berries of poison sumac (Toxicodendron vernix) are toxic. The poison sumac gives all sumac shrubs a bad name, even though most are quite harmless and beautiful in fall. Poison sumac has leaves made up of seven to 13 leaflets (always an odd number), a red stem, and white odd-shaped berries.

  • 08 of 22

    Poison Ivy

    Poison Ivy
    Ed Reschke/Getty Images

    Poison ivy's  (Toxicodendron radicans) toxic quality comes from an oil called urushiol. While the leaves are the most toxic element of the plant, contact with any part (even when bare of foliage) should be avoided to prevent a reaction. This also means you should not burn the plant because the smoke will also cause a reaction.

    Continue to 9 of 22 below
  • 09 of 22

    Easter Lily

    Easter lily flower

    The Spruce / David Beaulieu

    Gardeners in northern climates cannot expect Easter lilies (Lilium longiflorum) to bloom outdoors much earlier than July when most of the other popular lilies flower. (The ones you buy at the store have been forced to bloom for the holiday.) While the sap of the stems and leaves can be toxic to humans, Easter lilies and 'Stargazer' lilies are more problematic as they are very toxic for cats.

  • 10 of 22

    Stinging Nettles

    Closeup of leaves of stinging nettles.
    Judith Haeusler/Getty Images

    Like poison sumac and poison ivy, stinging nettles (Urtica spp.), as its name suggests, is not a plant you want to brush up against when working out in the yard. Don't confuse stinging nettles with dead nettles, a perennial used as a ground cover in shady areas.

  • 11 of 22

    Yellow Dock

    Close up of yellow dock

    byrev/Pixabay

    The ASPCA lists dock (Rumex sp.) as toxic to dogs. The toxicity to humans is low. Dock (also known as sorrel) is easy to identify late in the season. The mature flower head of a yellow dock plant looks like coffee grounds after its blooms have dried and assumed a brown color.

  • 12 of 22

    Lantana

    Lantana plant flowers.

    sylviaestock/Pixabay

    Lantana (Lantana camara) bears colorful flower clusters and is commonly used as an annual by gardeners in cold climates in hanging pots. Growers in warmer climates are familiar with lantana as a shrub, where this vigorous grower may even be invasive. But its invasiveness is not the only issue that comes with growing lantana: the berries, leaves, and sap are toxic.

    Continue to 13 of 22 below
  • 13 of 22

    Lily-Of-The-Valley

    Lily-of-the-valley plant

    Happynut/Pixabay

    Lily-of-the-valley (Convallaria majalis) is a traditional wedding flower. Its flowers are bell-shaped, fragrant, and white. From a landscaping perspective, lily-of-the-valley can become a problem because it is invasive. Despite its delicate and romantic appearance, lily-of-the-valley is toxic in large amounts.

  • 14 of 22

    White Baneberry

    White baneberry with its pinkish-red stems.

    The Spruce / David Beaulieu

    Whenever you see the word "bane" in a plant name, chances are excellent that the plant is toxic. Baneberry (Actaea), an herbaceous perennial that belongs to the buttercup family, comes in both a red and a white form. If its toxicity is not enough to scare you, stare into the spooky "doll's eyes" of the white form.

  • 15 of 22

    Tansy

    Closeup of flowers of tansy plant.

    sola deo gloria/Getty Images

    Common tansy (Tanacetum vulgare) was once a much-valued herb that has now fallen from grace. It is a perennial that is often grown simply for its golden flowers, which are numerous and look like cute little buttons. When ingested, it's toxic to people and animals, and especially livestock. It's common to mistake tansy and equally toxic tansy ragwort (Jacobaea vulgaris) for each other since they look similar.

  • 16 of 22

    Poison Oak

    Poison oak leaves

     Darren415 / Getty Images

    Poison oak (Toxicodendron diversilobum), like poison ivy, has three leaves, making it easy to identify. The leaves are also shaped like those of an oak tree. The leaves redden in the autumn, and then the plant produces white berries. Though it's not the easiest toxic plant to eradicate, the best method is to pull it out manually by its roots while wearing protective gear or using herbicides while the plant is in active growth mode. If touched, a severe skin rash typically develops.

    Continue to 17 of 22 below
  • 17 of 22

    Oleander

    getty-oleander_1500_117966878.jpg

    Ursula Alter / Getty Images

    Oleander (Nerium oleander) is an easy-growing, pretty, and fragrant flowering shrub used for hedging and other places in the landscape. It's also highly toxic when touched or eaten by humans and animals. Plant oleander far away from gardens or areas of play that children or pets may use. Even when planting this bush, wear protective clothing and gloves to avoid direct contact.

  • 18 of 22

    Mistletoe

    Sprig of mistletoe with leaves & berries (medicinal plant)
    Jurg Waldmeier / Getty Images

    The many types of mistletoe lead a double life. It's used as a traditional holiday decoration and it's also a parasitic broadleaf evergreen that attaches to trees and shrubs, growing in unsightly balls.

    Though mistletoe (Phoradendron spp., Viscum spp., Arceuthobium spp.), in general, is thought of as a festive plant, some types are more toxic to humans and animals than others when ingested. For example, American mistletoe (Phoradendron serotinum) may not be quite as toxic as European mistletoe (Viscum album). To be safe, keep any type of mistletoe out of reach from children and pets.

  • 19 of 22

    Jimsonweed

    white Jimsonweed blooming in the desert

    Jared Quentin / Getty Images

    Jimsonweed (Datura stramonium) is highly toxic to both humans and animals when it's ingested. The most distinguishing part about this nightshade family plant is its thick purple stems, large and attractive trumpet-shaped white or purple flowers, and a disagreeable odor that smells something like stinky feet. The plant has shallow roots and can easily be removed by weeding.

  • 20 of 22

    Poison Hemlock

    Front view of poison hemlock

    The Spruce / K. Dave

    Poison hemlock (Conium maculatum) is not only toxic to humans and animals if ingested in small amounts, but it is also classified as an invasive plant. It's not easy to identify because its appearance changes and other non-toxic plants look similar. In its first year, it will produce white umbrella-like flowers resembling Queen Anne's lace. But the easiest way to identify this plant is in its second year when the hollow, hairless stems have telltale reddish-purple streaks and spots.

    Seedlings are easy to remove but an infestation takes more diligence by mowing and using chemicals to weaken the plants. Never burn or compost this plant. It should always be properly disposed of in a sealed garbage container.

    Continue to 21 of 22 below
  • 21 of 22

    Wild Parsnip

    Wild parsnip plants with yellow flowers

    KathrynSK / Getty Images

    Wild parsnip (Pastinaca sativa) is a tall plant with characteristic yellow flowers and leaves that appear celery-like. Oftentimes wild parsnip grows among poison hemlock, creating a sea of yellow and white umbrella-like flowers. Wild parsnip should never be touched as it is highly toxic to humans and animals.

  • 22 of 22

    Giant Hogweed

    Giant hogweed plant with brown flat-topped flower clusters on thin stems closeup

    The Spruce / K. Dave

    Giant hogweed (Heracleum mantegazzianum) grows tall to about 15 or 20 feet in height and often produces clusters of white flowers that resemble Queen Anne's lace. However, giant hogweed looks similar to poison hemlock in that it will have stems with purple spotting but it will also have some hair growth. The leaves of giant hogweed look very different from poison hemlock; they are not lacy but are large and deeply incised. The plant is extremely toxic to touch for both humans and animals.

What to Do If You Touch a Poisonous Plant

Here's what to do if you touch a toxic plant:

  • Immediately rinse your skin with rubbing alcohol, poison plant wash, or a degreasing dishwashing soap or detergent, and lots of water. Scrub under your nails using a brush. Keep rinsing and do it frequently so none of the solutions you are using dry on your skin or spread the urushiol (oily resin in poisonous plants).
  • Apply wet compresses, calamine lotion, or hydrocortisone cream to the skin to reduce itching and blistering.
  • Seek immediate medical attention if you have a severe allergic reaction, difficulty breathing, or swelling on your body or face.
FAQ
  • What plant is the most toxic to humans?

    Belladonna (Atropa belladonna) is considered one of the most toxic plants to humans and animals, mostly because of its sweet-tasting fruit. It is not the most common plant, thankfully. In the United States, belladonna has been found in only a few states, growing in wastelands and areas with disturbed soil, such as dumps, quarries, and roadsides. Monkshood is one of the most dangerously toxic plants found in garden landscapes. It is toxic if ingested and may be fatal to humans and pets. Gardeners are advised to wear gloves when handling it in any way. Foxglove, listed above, is another plant noted to be most toxic to humans.

  • What are some common characteristics used to identify poisonous plants?

    One common characteristic used to identify poisonous plants, like poison ivy and poison oak, is the number of leaves. These plants have three leaves budding from a stem. However, the characteristics of other poisonous plants can vary. It helps to identify the poisonous plants common during each season in your area.

  • What is a common plant that is toxic to pets?

    Many common plants are toxic for pets, including bulbs like lilies, autumn crocus, tulips, hyacinths, and daffodils in addition to shrubs like oleander. and wildflowers like lily of the valley. Common houseplants toxic to pets include snake, jade, pothos, philodendrons, and dumb cane plants. This is only a short list of the many common plants that are not safe for pets.

The Spruce uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Solanum dulcamara L. United States Department of Interior.

  2. Safe and Poisonous Garden Plants: Toxic Plants. University of California.

  3. Digitalis purpurea. North Carolina State University Extension.

  4. Azaleas and Rhododendrons: Identify and Manage Problems. University of Maryland Extension.

  5. Salihu, Bolaji, Gana, A.K., Apuyor, B.O. Castor oil plant (Ricinus communis L.): Botany, ecology and uses. International Journal of Science and Research, vol. 3, pp 1333-1341, 2014. 

  6. Yew and Paclitaxel. National Capitol Poison Center.

  7. Poison Ivy, Oak, and Sumac: When Does the Rash Appear? American Academy of Dermatology Association.

  8. Lovely Lilies and Curious Cats. U.S. Food and Drug Administration.

  9. How to Identify Iowa's Poisonous Plants. Iowa Dept. of Natural Resources.

  10. Dock. ASPCA.

  11. Rumex crispus (Curled Dock). North Carolina State University Extension.

  12. Stegelmeier, Bryan L., Field, Reul, Panter, Kip E. Hall, Jeffrey O. et al. Selected Poisonous Plants Affecting Animal and Human Health. Haschek and Rousseaux's Handbook of Toxicologic Pathology (Third Edition), vol 2, 2013. doi:10.1016/B978-0-12-415759-0.00040-6

  13. Lily of the valley is very poisonous. National Poison Control Center.

  14. Baneberry. University of Wisconsin Division of Extension: Horticulture.

  15. Common Tansy. Minnesota Department of Natural Resources.

  16. Ragwort. ASPCA.

  17. Outsmarting Poison Ivy and Other Poisonous Plants. FDA.

  18. Nerium oleander. North Carolina State University Extension.

  19. Oleander. ASPCA.

  20. Keep Your Pets Safe from These 10 Holiday Hazards! ASPCA.

  21. Is mistletoe poisonous? National Capital Poison Center.

  22. Jimsonweed. West Virginia University Extension.

  23. Weed of the Month: Jimson Weed. Brooklyn Botanic Garden.

  24. Poison Hemlock. U.S. Department of Agriculture Agricultural Research Service.

  25. Poison Hemlock. Invasive Plant Atlas of the United States.

  26. Poison hemlock identificaton and control. Michigan State University.

  27. Be Alert to Wild Parsnip. Ohio State University.

  28. Wild parsnip: problem plant in hay and pastures. University of Minnesota Extension.

  29. Giant hogweed. ASPCA.

  30. Heracleum mantegazzianum. USDA.

  31. NIOSH Fast Facts: Protecting Yourself from Poisonous Plants. CDC.

  32. Aconitum. North Carolina State University Extension.

  33. Identifying Poisonous Plants. CDC.