Antony Worrall Thompson grows many herbs and vegetables for his restaurant
Celebrity chef Antony Worrall Thompson has apologised after he recommended use of a poisonous plant in recipes.
In a magazine interview about watercress and other wild foods, Mr Worrall Thompson said the weed henbane was "great in salads".
Healthy & Organic Living magazine's website has now issued an urgent warning that "henbane is a very toxic plant and should never be eaten".
The chef had meant to recommend fat hen, which is a wild herb.
Mr Worrall Thompson, currently on holiday in Spain, told the BBC the mix-up was "embarrassing - but one of those genuine mistakes".
Henbane - Hyoscyamus niger - has sticky serrated leaves, yellow, funnel-shaped flowers and a stale scent.
Its name has Anglo-Saxon origins - meaning killer of hens - and it can cause hallucinations, drowsiness and disorientation in humans.
Larger quantities can cause a loss of consciousness, seizures, trembling of the limbs and, in extreme cases, death.
The television chef said the poisonous weed has a "nasty history".
"Henbane is associated with lots of mythical tales - it's said to turn you black and it's used in witches potions," he said.
But fat hen is perfectly edible.
"You can use the leaves in salads like spinach, make tea and eat the roots," said Mr Worrall Thompson.
He is unsure how the mistake happened.
"It's a bit embarrassing but there have been no reports of any casualties. Please do pass on my apologies."
Healthy & Organic Living magazine's editor Kate Collyns has written to subscribers to apologise.
Her publication's website gives this advice: "As always, check with an expert when foraging or collecting wild plants."
The interview with Mr Worrall Thompson is in the August issue.