Yew

The yew plant is found all over the world and has a rocky history. Ancient cultures referred to this plant as the “tree of death,” because it may cause cardiac arrhythmia if ingested. It will completely stop your heart and cause death. Animals are very susceptible, and if they ingest yew, they’ll die within 24 to 48 hours. Its poison comes from its highly toxic alkaloids, which are found in high concentrations of the leaves in wintertime (Mount Sinai).

Deadly Nightshade

The name says it all. The deadly nightshade is deadly and is one of the most poisonous plants in the world. This is due to the alkaloids found in its berries, roots, stems, and leaves. Not only is ingesting it poisonous, which may cause death if ten to twenty berries are ingested by an adult but even rubbing against it irritates the skin. If ingested, other symptoms include enlarged pupils, dry mouth, vomiting, stomach pain, diarrhea, slowed breathing, delirium, and paralysis (Best Life Online).

Angel’s Trumpet

Stay far away from the angel’s trumpet, even if its name sounds inviting. It has bugle-shaped flowers and is very beautiful to look at, but incredibly toxic if ingested. If accidentally ingested, users will experience difficulty swallowing, thirst, vomiting, diarrhea, hallucinations, loss of consciousness, and eventually, delerium. Even the perfume alone is enough to cause a negative reaction, which includes headaches, nausea, and lightheadedness (Sharp).

Tansy

People often grow tansy for its golden, bright, vibrant flowers, and by looking at this photograph, you can probably see why. It’s symbolic of summertime and happiness. Even though tansy has previously been historically used for flavoring, it contains a toxic essential oil that may kill a human. If it doesn’t kill you, it will cause liver and brain damage, and at the very least, an allergic reaction to those who touch the flower. There’s a reason we don’t recommend growing these beautiful flowers in your backyard. The risk isn’t worth the reward (Growveg).

Rhubarb

Rhubarb pie might be your favorite dessert in the world, but there’s only a small amount of rhubarb that can be used. Ingesting large amounts of this plant’s leaves can kill you. It’ll cause nausea, difficulty breathing, and kidney stones. This is due to the deadly oxalic acid, which will eventually cause kidney failure. Luckily, you’ll need to consume 12 pounds of rhubarb to get sick, which is very unlikely to happen. You can safely put the rhubarb leaves in your compost, though, because oxalic acid isn’t absorbed by the leaves (Taste Of Home).