The head gardener at the internationally renowned Alnwick Poison Garden, Trevor Jones, revealed to Express.co.uk the unassuming evergreen could actually be incredibly dangerous – and that most people were completely unaware of its nasty secret. He explained that the culprit was laurel – used most often as hedging – which went trimmed became lethal. He said: “A lot of people grow laurel hedges – it’s an evergreen, it’s great for hedging.
“And they all clip their hedging and they’ll take their hedging away to the dump.
“But laurocerasus produces cyanide.
“Victorians were great at creating death jars and they did that by getting a jar and getting a laurel leaf, cutting it in half, popping half into the jar, catching a butterfly and putting it in the jar with the lid on top.
“And the butterfly dies because the cyanide given off by the leaf starts to build up.
“We’ve had visitors that go through our poison garden and say, ‘oh yeah, I’ve got a laurel hedge and I cut it and I put it in my car.
“And I’ve got to drive three miles to the dump.
“And as I go, I always get a headache.’
“That’s because your brain is getting starved of oxygen – that’s what cyanide does.
“We had one gentleman that admitted he actually crashed his car on the way to the dump.
“He hit a lamppost, didn’t know why, but then after a bit of further investigation decided that, yes, it was the cyanide building up in the back of his car.”
The Poison Garden’s site explains that cherry-laurel water made by the distillation of the leaves was once used as a means of suicide.
In his ‘Treatise on Poisons’, published in the 1840s, Sir Robert Christison, writing about the various plant sources of hydrocyanic acid says “they have been repeatedly taken by accident; they have often been resorted to for committing suicide, and they have likewise been employed as the instruments of murder.”
The site explains: “Christison illustrates his point about accidental consumption with the story of a chemist’s servant who drank a large glass of hydrocyanic acid, thinking it was a liqueur after her master had left it out by mistake. She died within two minutes.”