Britain's Duchess of Cornwall was given the world's most expensive salad at the Hampton Court Palace Flower Show.

Camilla, the wife of Prince Charles, was shown around Anglian Home Improvements' 'Naked Garden' exhibit by its designer, landscape designer David Domoney, and was "fascinated" to learn about the hydroponically grown lettuces and tomatoes which were used in the dish, which costs a staggering £399.

David said: "Camilla was thrilled to see all the plants on display which are incredibly expensive because they are grown hydroponically. They are grown without SOiL and water and nutrients are sprayed direct to The Roots. But also this means that the plants on display are all kept alive right till the point they are put in the salad so this is the freshest green salad you will ever eat.

"Unfortunately it is also the most expensive as the growing of the plants like this is very labour intensive." 

There are several plants on display in the 'Naked Garden', including lettuces, which have been specially grown in laboratories in Holland and cost a huge £300 each.

The plants - which have been sourced from America, Brazil, Netherlands and Thailand - grow without soil and are being housed in a series of glass containers and transparent materials.

David explained, "Plants will be grown soil free so all the containers we use will be transparent with water solution inside enabling everyone see what is above and below the water level.  The plants will be getting their pots off through the challenging technology of aquatic culture that creates plants with exposed roots."

David's new TV show, 'Garden ER' launched on Channel 5 on July 13.