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Alnwick Garden - The Alnwick Garden is a complex of gardens around Alnwick Castle in the historic market town of Alnwick in Northumberland, England.

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Grand Cascade - The Garden is home to the Grand Cascade, an enormous fountain containing 120 water jets.

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Alnwick treehouse - At the Alnwick Garden, you'll also find one of the largest wooden treehouses in the world.

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Enter the Poison Garden -

Behind these gates, you'll find the Alnwick Garden's most intriguing tourist attraction.

(Photo: Flickr/CC BY-NC 2.0)

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Who created the Poison Garden? - The Poison Garden was started in 2005 by Jane Percy, Duchess of Northumberland.

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Inspiration - The Poison Garden was inspired by the Orto Botanico di Padova, a botanical garden in Padua, Italy.

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Visitors - Visitors must follow specific instructions when visiting the garden.

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Visiting the garden - Visitors are not allowed to touch, smell, taste, or even stand too close to these plants.

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Visiting the garden - Visitors can only go in as part of a guided tour. These have a limit of 20 people, so that the guide can supervise everyone.

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Caged plants - Some plants are so dangerous that they're secured in cages.

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Trained gardeners - Gardeners are specially trained to tend to the garden. They have to wear gloves and even masks when dealing with certain plant species.

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Ricinus - This plant, commonly known as the castor bean or castor oil plant, contains the lethal poison ricin. It's one of more than 100 deadly species that can be found in the Poison Garden.

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Hemlock - This highly poisonous plant also adorns the Poison Garden.

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Ruta graveolens - Commonly known as rue, this plant can give you a rash if you touch it.

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Belladonna - Belladonna, also known as deadly nightshade, can also be found in the Garden.

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Laburnum - All parts of laburnum, also known as golden chain or golden rain, are toxic.

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Brugmansia - Also known as angel's trumpets, these eye-catching flowers are, in fact, poisonous.

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Hellebore - Hellebore is another beautiful yet toxic flowing plant that can be found at the Poison Garden.

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Foxglove - Inhaling the pollen of this flower can be enough to trigger poisoning symptoms.

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Vinca rosea - Also known as the Madagascar periwinkle, this plant is actually used in chemotherapy.

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Nux vomica -

Otherwise known as the strychnine tree, ingesting its seeds can have harmful effects.

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Euphorbia -

Euphorbia, or spurges, are highly toxic. Touching them can give you a nasty rash.

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Vinca major - Also known as greater periwinkle, this plant has been used to treat low blood pressure.

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Drug awareness - The aim of the Poison Garden is also to create awareness of the dangers of illicit drugs.

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Tobacco - Tobacco, which is used in harmful products such as cigarettes, is also planted at the Poison Garden.

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Cannabis - Cannabis sativa plants are seen here at the Poison Garden. The warning sign is quite appropriate.

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Coca - Coca plants are planted as part of the awareness against drug use.

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Opium poppy -

The plant, used as the base for the production of drugs such as heroin, can also be found at the Poison Garden.

See also: These plants and flowers can kill you.

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