Deadly beautiful: 7 UK flowers that harm more than heal
Discover the darker side of some of our most bewitching blooms
For centuries, people have been intrigued by pretty but potentially toxic wild plants, creating folklore around them and concocting strange "cures" that were often more likely to harm than heal.
Flowers could be particularly deceitful: despite their good looks, many blooms can be irritants at best and fatal at worst.
In the UK, we have more than 100 varieties of poisonous flowers in our woodlands and field margins.
If you consume any of these flowers, contact your local doctor immediately. Always take care when foraging or exploring open woodlands.
Here, we shine a spotlight on seven of the most surprising suspects…
Hellebore
Ancient cures were hit-and-miss affairs, but arguably no other plant had such potential to do harm in the wrong hands than hellebore.
Greek physician Ctesias, writing about the medicinal use of hellebores in the fifth century BC, noted: "If someone administered hellebore, he ordered the patient to draw up a will since he was going to be taking a serious risk. Many of those who took the drug choked to death while only a few survived."
And yet classical physicians continued to use it, convinced of its efficacy. Those suffering from melancholy, epilepsy and all manner of illnesses thought to be caused by "harmful humors" poisoning the brain were given hellebore infusions.
From classical times onwards, hellebore was also thought to cure a wide range of "women's problems," including unwanted pregnancy. Its administration would have, in most cases, been fatal for both mother and child, but the practice continued well into the 19th century.
Honeysuckle
Medieval writers were intrigued by honeysuckle’s habits and used its physical characteristics to craft allusions about human feelings and foibles.
As it grows, it twists and entwines its tendrils around other plants. So vigorous is its growth that it can sometimes smother the very thing it clings to. Modest by day, come the evening the flower springs into life, opening its petals and releasing its intoxicating scent.
It's no wonder, perhaps, that it also became a plant associated with sexuality and reproductive medicine. The berries – now known to be poisonous – were thought to be especially powerful. Gathered, dried and swallowed every day for 40 days, they were believed to speed up childbirth in women, while honeysuckle leaves, taken for a similar period of time, would supposedly make men barren.
Buttercups
Shakespeare called them "cuckoo-buds", while in English rural dialect, buttercups were often referred to as "crazies", both of which tapped into an ancient folk belief that buttercups caused insanity.
While native buttercups won't make you go mad, they are certainly toxic to both humans and livestock if eaten – symptoms include burning of the mouth and gastrointestinal irritation.
Applied topically, buttercups can also cause blistering, a fact that wasn't lost on early physicians, who relished any opportunity to "draw out" illness through the skin using buttercup salves and poultices. Some varieties of buttercup, however, are more toxic than others.
In Sardinia, the Ranunculus sardous, or hairy buttercup, is deadly and may have given rise to the phrase "sardonic grin". Anyone foolish enough to eat the flower, or have it forcibly administered, would find that the toxins in the buttercup caused their facial muscles to contort into a horrible smile, usually followed by a lingering death.
Bluebells
A plant that thrives in dark woodland, bluebells were once thought of as "fairy bells" capable of luring people into forest clearings, where they might fall asleep intoxicated by their perfume or, worse, disappear.
In Scottish lore, children who wandered alone among bluebells would be taken by fairies, never to be returned. A plant of such magical potency was also a useful tool for the superstitious healer.
Bluebells actually contain toxic glycosides that are poisonous to humans and animals, causing serious stomach upset and, in large quantities, can prove fatal. Their sap also causes skin irritation.
That didn’t stop physicians and folk healers from prescribing its viscous, glue-like juice as a diuretic or boiling up its roots to create a "cure" for snake and spider bites. Bluebell seeds dropped in wine were also thought to prevent the "falling sickness" (epilepsy) and the “bloody flux” (dysentery), a medicine that would have almost certainly made both conditions even more grave.
Lily of the valley
Generations of woodland walkers have loved the heady scent of lily of the valley. Unfortunately, just like bluebells, this seductive plant contains glycosides that can cause nausea, vomiting, blurry vision and potentially fatal heart problems.
Its leaves also bear an uncanny resemblance to wild garlic, creating potential for a deadly case of mistaken identity. In the past, those foolhardy enough to mess with lily of the valley's potency created a strange array of folk remedies.
John Gerard's late 16th-century Herball prescribed a treatment for gout, which involved filling a glass with water and lily of the valley flowers, placing it upon an anthill for a month, and then guzzling it down.
Even into the Victorian period, lily of the valley was believed to have healing properties, despite its acute toxicity. It was thought to make an excellent hand cream, its flowers pounded and gently heated with lard and wine, giving the flower its other folk name "glovewort".
Daisies
While many poisonous flowers were administered in the hope of doing some good, one flower – the common daisy, Bellis perennis – was used explicitly for harm.
Once again, physician John Gerard had some eccentric suggestions for its uses, including a claim that daisy roots "given to little dogs with milke keepeth them from growing great".
Small lapdogs were popular with nobility during the Elizabethan era; breeders tried many different ways of artificially stunting the growth of dogs to keep them tiny, including potent herbal concoctions.
Both daisies and another native British flower, knotgrass, were given to children in the hope of keeping them deliberately small, so they could be put to work earning money at fairs and sideshows.
Foxgloves
Foxgloves can be deadly. And yet, for centuries, they were one of the most important flowers in folk medicine.
A compound found in foxgloves, digoxin, is now known to manage certain heart problems, but as early as the 13th century, physicians were blindly prescribing foxglove preparations for everything from tumours to violent headaches, oedemas to stomach cancer.
In reality, the difference between a therapeutic dose of digitalis and a lethal one is so slim that most folk "cures" must have killed as many patients as they saved.
One of the most famous patients was van Gogh, whose epilepsy was treated with a drug made from foxglove leaves during a hospital stay.
Foxgloves have no effect on fits and wouldn’t have helped poor Vincent, but some art historians believe it may have influenced his artistic output; one of the lesser-known side effects of digitalis is a change in colour perception.
I'm a smallholder, Country Living columnist and expert in rural living, residing in North Yorkshire.
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