In 2014, a gardener on a country estate in the UK mysteriously died of multiple organ failure.
The cause of his death remains unclear, but an inquest heard evidence suggesting he had been killed by a popular flowering plant, a member of the buttercup family.
The plant in question, called Aconitum, has blooms said to resemble monk’s hoods. But the plant is also known by other more sinister names; wolf’s bane, Devil’s helmet and the Queen of Poisons.
These do more than hint at its villainous reputation. For Aconitumis among the most deadly plants in the world.
The most poisonous part is the roots, though the leaves can pack a punch too. Both contain a neurotoxin that can be absorbed through the skin. Early symptoms of poisoning are tingling and numbness at the point of contact or severe vomiting and diarrhoea if it has been eaten.
In 2010, Lakhvir Singh was convicted of the murder of her lover after dosing his curry with Indian aconite. Apart from causing severe gastrointestinal upset, the poison slows the heart rate which can result in death.
But not every case is so unfortunate. According to former poison garden warden and expert John Robertson, our excellent vomiting mechanism means people can live to tell their tales.
“I’ve spoken to people that have eaten it and survived,” says Mr Robertson. “It was a couple that planted it to make their herb garden look prettier and when the wife was picking leaves for a salad she picked a few leaves of monk’s hood. They both had a pretty bad time of it for 24 hours but survived.”
The popular theory is that toxins have evolved in plants as a defence. In certain species, chemical compounds that are produced to fight off insect pests and other micro-organisms can do damage to big animals too.