Britain's deadly blooms: A visit to the Poison Garden

A unique experience awaits horror enthusiasts on the British Isles. Visitors are greeted by a warning sign that reads, "These plants can kill." The iron gate is further adorned with skull symbols. Behind it lies the most poisonous garden in the world, which can be toured.

The Poison Garden is a section of Alnwick Garden, established in 2005 in Northumberland, in North East England. The garden can only be visited with a guide.

- Before visitors are allowed to enter, they must have a safety briefing, - explains Dean Smith, a garden guide, in an interview with BBC Travel. He explained that the visitors are strictly warned not to touch, smell, or taste any of the plants.

The Poison Garden features over 100 species of plants, including those with potent poisonous, narcotic, or hallucinogenic properties. The official garden website mentions instances of people fainting after disregarding recommendations and inhaling volatile toxins.

One of the most dangerous plants in the garden is aconite, also known as wolfsbane, which contains aconitine, a potent neurotoxin.

The most deadly plant, however, belongs to another species. - Probably the most poisonous plant we actually have here is ricin, better known as the castor bean or castor oil plant, claims Smith. - The Guinness Book of World Records considers that to be the world's most poisonous plant, - he adds in an interview with BBC.

Some plants, such as the popular rhododendron, are cultivated in homes and also contain potent toxins like grayanotoxin. Another example is the common laburnum, a beautiful tree whose flowers and seeds are rich in cytisine. -The tree is so poisonous that if one of the branches was to fall to the floor, lay there for several months and the dog later comes along, picks it up to hold as a stick on a walk, chances are the dog won't finish the walk. It's that poisonous. - says Smith. He added that it's the second most poisonous tree in the UK.

However, you don’t need to touch the plants to be in danger. For some, simply being near them, such as during pruning, can put you at risk. For instance, the leaves of cherry laurel contain cyanogenic glycosides, which release cyanide ions.

Smith explains that on their own, these glycosides pose no threat to humans. However, when the leaves are crushed, they release hydrogen cyanide. He adds that while the risk is negligible in open air, it becomes greater if the leaves are kept in a confined space or burned.

Inhaling hydrogen cyanide is lethal. How do garden staff protect themselves from these dangers? In an interview with BBC Travel, Robert Ternent, the head gardener at Alnwick, emphasises that safety comes first. He adds that this can involve wearing gloves and, in some cases, full protective gear, including a suit, mask, and gloves.

The garden can only be visited with a guide. Entry to this extraordinary part of the complex costs £18.95. Youths under 16 enter for free but must be accompanied by an adult. One adult can bring four children. The fifth and each subsequent child pays an entry fee of £6.60. For safety reasons, entry with animals, except for guide dogs, is prohibited.

Remember that the Poison Garden is only part of the Alnwick complex, established in 1750. It also features the world’s largest treehouse, a cherry orchard, a serpentine garden, and numerous fountains. Tickets to the garden do not include the entry fee to Alnwick Castle.