It is a plant so deadly, yet so innocuous, that it regularly features in crime fiction murder plots.

Now, a mum has warned other parents to be on the lookout for hemlock after her two-year-old son ended up in hospital after taking a bite out of the poisonous plant.

Megan Joseph, of North Elmham, near Dereham, was sitting in her garden with partner Richard McKay and their son, Richard junior, when the toddler picked up what looked to be a white flower and decided to have a taste.

The pair had only taken their eyes off the youngster for a split second, but it was enough time for him to pick the plant and bite it.

They were able to get the boy to spit the plant out, but feared the damage could have been done and immediately phoned 111.

Miss Joseph, 28, said: "Big Richard works in gardening so thank God he was there and was able to get him to spit it out, but given how tiny the flowers are we are sure he must have swallowed some, so rang for help straight away.

"We ended up having to take Little Richard to A&E where he was observed for five hours and thankfully was okay - but the doctor told us if he had swallowed the whole thing within two or three hours he could have ended up with paralysis or in cardiac arrest.

"Since then I've been reading up about it and there are real horror stories about people who have eaten it, so it's really worrying."

While Little Richard was in hospital, Big Richard went around and collected all of the plants from the garden and disposed of them.

Now, Miss Joseph is urging other parents to look out for the plants in their own gardens and out and about.

She said: "They can look quite similar to cow parsley, which is okay to eat, but have no hair on the stem, while cow parsley is quite fuzzy.

"We watch Little Richard all the time but with toddlers, it can be really hard to stop them from putting things in their mouth. So the best thing to do if they eat something you aren't sure about is ring 111 and get help as soon as you can."

What is hemlock?

Eastern Daily Press: HemlockHemlock (Image: Archant)

Hemlock is a notoriously poisonous plant which produces umbrella-like clusters of flowers in the summer.

According to the Wildlife Trust is generally found in damp places like ditches, riverbanks and waste grounds, but is classified as common and also be found in roadside verges.

It is a tall, upright plant and can be recognised by its distinctive, mousy smell and purple-spotted stems.

Similar species include cow parsley, yarrow and fennel.

It is classified as a Class B noxious weed and its poison has earned it notoriety.

The plant's poison was famously used in the execution of Greek philosopher Socrates and also features as the murder weapon in an Agatha Christie novel.