Common plants that are toxic

Throughout the ages plants have provided us with many things: food, shelter, warmth, fuel, medicine, clothes, textiles, entertainment and a love of nature. With many of the species of plants around today, toxicity is an important aspect that must be addressed – especially when the toxicity involves a plant you are already quite familiar with.

One of the most well known ornamental plants around Christmas time is the poinsettia. Euphorbia pulcherrima is a plant native to the tropical, deciduous forests of Mexico. This is due to its distinctive red and green leaf combinations

Common plants that are toxic
Poinsettias are not extremely poisonous as are most other plants in the Euphorbia genus. While ingestion can cause vomiting and diarrhoea, exposure can cause temporary skin eczema and contact with the eyes can cause temporary blindness, this is not always the case.

English Ivy is an extremely common plant and it is often used by gardeners as an edge plant, or in the home as an intriguing houseplant.

Young children are often victim to this plant’s poison, most likely due to its curious demeanour. Ingestion can cause delirium, stupor, convulsions, hallucinations and fever, and contact with its leaves can cause skin irritation, itching, rash and blisters.

Easter lilies are a very common species in the Liliaceae family. Although native to the Ryukyu Islands of Japan and Taiwan, this lily is found in gardens all across the world. Growing up to one metre in height, and bearing a number of trumpet shaped, white, fragrant and outward facing flowers, it is a keepsake to the art of gardening.

Easter lilies, although beautiful, are also poisonous, especially to cats, at an extreme level. It is also poisonous to humans due to the alkaloid Lycorine, found in the bulbs and stems. Symptoms of poisoning due to ingestion of Easter lily (likewise for almost all other true lilies) include abdominal pain, salivation, shivering, nausea, vomiting and diarrhoea.

Larkspur is a member of the buttercup family Ranunculaceae, and is native to North America. From 10 centimetres and in some alpine species, up to two meters tall, this plant is topped with a raceme of many flowers, varying in colour from purple and blue, to red, yellow or white. Almost all species are toxic. Despite its toxicity, Delphinium species are used as food plants by the larvae of some moth species.

Symptoms of poisoning include burning of the lips and mouth, numbness of throat, intense vomiting and diarrhoea, muscular weakness and spasms, weak pulse, paralysis of the respiratory system and convulsions, which usually leads to death. Although it is a genuinely attractive plant to look at, it is best left alone.

Azaleas are a very common plant, found in gardens all over the world. Its evergreen leaves and brilliant flowers make it an exceptionally attractive plant for many gardeners. Its flowers are white to deep pink, red, yellow, purple, blue and orange.

Common plants that are toxicDespite its popularity, an underwhelming common knowledge of its toxicity exists. All parts of the Rhododendron are highly toxic, and may be fatal if eaten. Symptoms from ingestion include over-salivation, watering of eyes and nose, abdominal pain, loss of energy, depression, nausea and vomiting, diarrhoea, weakness, difficulty breathing, progressive paralysis of arms and legs and coma, usually leading to death.

Oleander is a small, yet eye-catching plant, and its flowers are known to come in a wide assortment of colours. Grown mainly in Mediterranean regions one aspect of the plant is its high level of toxicity. A single leaf consumed by an infant or child is often fatal. It is even known to hold its toxicity after drying. The symptoms experienced from the ingestion of this plant are horrific and terrifying. These include nausea, stomach pain, dizziness, drowsiness, poor circulation to extremities, seizures, tremors, collapse, slowed pulse, irregular heartbeat, pupil dilation, bloody diarrhoea, coma, death and suicidal depression.

Foxglove is a beautiful plant that is common in many colourful gardens. Its scientific name, digitalis, means “finger-life” and refers to the ease with which the flower can be fitted over a human fingertip. These flowers, produced along a tall spike, are known to come in colours such as blue, purple, pink, white and yellow. They also sometimes possess various markings and spots inside the flowers..

Initially praised for its medicinal effectiveness with treating heart conditions, epilepsy and other seizure disorders, many of its uses are now considered inappropriate, due to its wide variety of adverse reactions. The entire plant is toxic, though the leaves of the upper stem are particularly potent. Just a nibble has the potential of causing death. Early symptoms of ingestion include nausea, vomiting, diarrhoea, abdominal pain, wild hallucinations, delirium and severe headache. Depending on the severity of toxicosis, a victim may later suffer irregular and slowed pulse, tremors, cerebral disturbances (especially of a visual nature, such as colours appearing yellowish to green, and blue halos around lights), convulsions and deadly disturbances of the heart. Sadly, death is often at the end of many experiments with foxglove.

Images: © David Kay |