Fllowers of Evvil Traditionally, Valentine’s Day consists of flowers being given to express one’s love for another. Roses are popular for this occasion. However, beautiful as they may be, there is a darker side to some flowers, many of which are indeed given in various bouquets or kept in our gardens. Many toxic plants evolved their poisons as an avoidance mechanism from hungry herbivores, and as we will see, they have often been effective. These plants have been used throughout history for various purposes ranging from recreational to cosmetic, to downright dastardly. These ‘flowers of evil’ often have a fine line between helpful medicinal properties and toxicity. Many serve as star attractions in so-called ‘poison gardens’ where they are kept as unusual commodities, the most famous of these being Alnwick Garden in England owned by the Duchess of Northumberland. She has stated rather sinisterly that it is “much better to know how a plant kills” than what medicinal properties it has. Many of these flowers provide an interesting insight into the ancient and ongoing relationship between plants and people, as we delve into the realm of (potentially) fatal flora. The foxglove is one such plant. With its beautiful pink, purple or white bell-shaped flowers, it is often kept as a showy addition to any garden. All foxglove species contain a cocktail of potent toxins, including digoxin and digitoxin. Within the human body, an overdose of these toxins can wreak havoc with the cardiac system in even the healthiest human, causing arrhythmias – unusual heart rhythms – as well as increasing the potassium levels in the blood to the point of fatality. In addition to cardiac problems, foxglove overdose can cause severe pain in the digestive tract as well as hallucinations. Often, a victim of an overdose will suffer from these symptoms for around 5 days before effects subside, but death is also a distinct possibility. The potential for misuse of these flowers for recreational use was identified as early as 1785, and there was a spate of cases of overdose of foxgloverelated toxins, both deliberate and accidental as recently as the 1970s, due to the herbal tea craze. However, such compounds (known collectively as glycosides) have been historically used in small doses to aid various heart conditions, such as congestive heart failure. In modern medicine, glycosides tend to be overlooked in favour of alternatives due to there being no evidence for an increase in survivability of patients with these conditions. On the contrary, they may still be used in low doses to treat arrhythmias. Glycosides are not unique to the foxgloves, however. They are present in many other plants, but often fulfilling different roles thus making them a little safer (and occasionally more dangerous) for human consumption. A flower which is as toxic as it is culturally important is the lily (species of the genus Lilium). Lilies are very attractive flowers that are often given as gifts or are out in the garden. They represent purity and have a deep-seated basis in religion. In Christianity for example, lilies are popular plants for Easter services as a floral representation of Jesus’ resurrection. This historic view of the lily as a symbol of purity even goes as far back as ancient Greece and they are still important in Greek wedding ceremonies. However, these stunning flowers have a darker side for the cat owners out there. They are highly toxic to cats and ingestion of two petals is enough to be fatal, although all parts of the plant are dangerous, including the pollen. The somewhat terrifying aspect of lily poisoning is that the way that the toxins work is unknown. However, the symptoms that occur are related to kidney failure, the onset of which is not immediate but generally between two and three days. Due to this, if your cat has even suspected to have ingested lily it is a veterinary emergency and time really is of the essence in this situation. True lilies tend not to be so fatal to humans, but other species labelled as lilies, for example, the peace lily is very poisonous to cats, dogs and humans. Ingestion can cause swelling of the mouth and tongue, which can block airways and cause death. It is therefore prudent to keep anything labelled as a lily out of the reach of pets and children. Several seemingly innocuous and popular garden residents are extremely poisonous. Spring brings with it the flourishing of bright yellow daffodils. Not a flower we would likely equate with toxicity due to their favourable representation in art, poetry and prose, but these plants, along with other members of the Narcissus genus, contain a variety of alkaloids including the poison lycorine. Lycorine is most commonly found in the bulbs of daffodils but may also be present in smaller quantities throughout the plant. Superficially, the bulbs are very similar to those of onions and there have been cases of people confusing the two, leading to accidental ingestion. As with lilies, the actual mechanism of toxicity and metabolisation is not known. Lycorine is known however to prevent neurotransmitters from working adequately and also highly suppresses protein synthesis. Whilst small doses are generally a minor inconvenience and symptoms such as nausea are resolved quickly, high doses can be fatal. When we think of dangerous flowers, the plant Atropa belladonna often springs to mind. Its species name means ‘beautiful lady’ in Italian and is a stark contrast to its common name and one you will likely know is deadly nightshade. Despite its name suggesting its effects (and is certainly an accurate name, this plant is one of the most poisonous found in Britain), the deadly nightshade plant has been used extensively throughout history. There are stories of early humans as well as the Romans using it as a poison both to hunt and to commit some rather nefarious deeds. Famously, Emperor Augustus’ wife, Agrippina, is thought to have used this plant to murder her husband. More commonly, women would use nightshade eye drops to dilate their pupils. Nightshade acts upon the eye as a muscular blocker and prevents the pupils from changing size in differing lights. Large pupils were seen as attractive, although blindness from overuse of this plant probably not so much. Nightshade is a strong hallucinogenic which may be appealing to some. Typically, curiosity kills the cat. Or human in this instance. It is highly recommended that people do not use this plant as a recreational drug due to its radical effects on the nervous system and high propensity to cause death. One of the main compounds in nightshade is called atropine and whilst this is, in fact, used as a genuine medical intervention for pesticide poisoning in both people and cats, overdoses can cause heart conditions, seizures and potentially coma. It also suppresses important parts of the nervous system responsible for the control of breathing and other essential activities. Belladonna is so deadly that just two of the sweet-tasting berries can be lethal for children. The deadly nightshade may sound a bit frightening but is not the most poisonous in the UK. That accolade falls to the unassuming native plant known as monkshood or wolf’s bane. Monkshood flowers are typically purple-blue or white in colour and as its name suggests, look like a hood.
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