You may be surprised to find that poisonous plants could lurk in your own backyard. Foxglove, a perennial common in landscaping, is particularly dangerous: If ingested, it causes severe nausea, abdominal pain, cramping, diarrhea and possibly even fatal heart problems. Other common garden plants -- azalea, black locust, colchicum, daphne, hellebore, hydrangea, lantana, lobelia and yellow Jessamine -- also have the potential to trigger mild to severe toxic reactions.
With pointy leaves and spiky fruit, jimsonweed (Datura stramonium) definitely looks the part of a poisonous plant. Its toothed foliage emits an unpleasant odor and branches from reddish-purple stalks, which grow to a height of 3 to 4 feet (0.9 to 1.2 meters). The plant's fruit is particularly wicked-looking. The green spheres, measuring about 2 inches (5 centimeters) across, are covered with long, sharp spines. Even the nectar and petals of its beautiful white or lavender trumpet-shaped flowers are dangerous. They, like the rest of the plant, are tainted with the toxins atropine and scopolamine.
European settlers in the New World quickly discovered the potency of jimsonweed, which grows throughout Canada, the United States and the Caribbean. The plant was plentiful at Jamestown, where some colonists made the mistake of having it for dinner as early as 1607. They would have experienced horrific symptoms, including dilated pupils, racing heartbeat, hallucination, delirium, aggressive behavior and possibly coma or seizures.
The plant has been linked to darker arts, like witchcraft and voodoo, because of its delirium-inducing and hallucinogenic properties. For most people, though, jimsonweed is a dangerously poisonous plant that's best avoided completely.