The Poisonous Garden

The Poisonous Garden

  • Complete: July 2018

  • Project Size: 650 sq m

  • Project Value: £130,000

Warnes McGarr & Co were approached by The RHS to design and project manage their main visitor exhibit for the RHS Tatton Flower Show 2018. The Poisonous Garden was an enormous immersive garden at 650 sq m, so careful planning and meticulous project management was required.

We began outline plans around February 2018, so we had plenty of time to invest in the fine detail in the later months. Landscape designer Rob spent a long time designing the hard landscaping elements, thinking carefully about the aesthetics, the theme and practical details, such as the flow of visitors walking around.

Five large timber shipping container-style units, wrapped in vinyls featuring anatomical drawings, provided an entrance to the garden, as well as port holes for the visitors to view the different garden sections. Vintage telegraph poles were used to create height, as well as providing a frame to hang sailshades across the seating area in the middle.

These elements gave an industrial and urban feel to the garden, providing the perfect setting and structure for the planting schemes. Signage had to be planned in throughout, including informative boards about the dangers of plants, which is not something we would usually have to consider either in a residential garden or a typical show garden.

Garden designer Michael did huge amounts of research about poisonous plants, driving up and down the length of the country to visit suppliers and specialists and other poisonous gardens.

The ultimate design consisted of four separate planting areas, separated by walkways, which were: Pretty Deadly; Hungry Plants; Apothecary and Plant Defence.

Pretty Deadly featured plants, many of which are common garden plants such as Digitalis purpurea and Aconitum carmichaelii ‘Arendsii’, which are extremely toxic and potentially deadly. Brugmansia, which can cause delirium and hallucinations and Ricinus communis, from which ricin is derived, were also displayed within the planting.

In addition to this, a huge caged Cycas revoluta was sectioned off as a centrepiece, and is poisonous if any parts of it are ingested, particularly the seeds, and has no known antidote.

Within the Carnivorous planting area, there was a stunning collection of Sarracenia, which digest flying insects, as well as Nepenthes, Drosera binata and Dionaea muscipula.

 The Plant Defence section investigated how plants use spikes or spines, for example, to protect themselves. In a nod to our gold award-winning RHS Tatton garden from 2017, we included the large Echinocactus grusonii, and some beautiful large Agave salmiana ferox, as well as plenty of more common British garden plants that have the ability to injure humans with their thorns, spikes and thistles.

The Apothecary section was absolutely fascinating to research and plan out the complex planting scheme. The extensive planting list included medicinal plants, which can be harmful if used in excess or can be healing if used in moderation.

The planting scheme included many herbs and medicinal plants as well as tree specimens of Ginkgo biloba; Aesculus hippocastanum and Vitex agnus castus.

 You can view the full and extensive planting list here:

The Poisonous Garden planting list