Couch potatoes are not usually found in the garden.

They are more at home on a dishevelled sofa staring listlessly at the television in the living room.

But a team of students have incorporated a grass couch, an old television set and a host of bizarre potatoes in an unusual garden design.

They hope it will impress judges at Hampton Court Flower Show and challenge couch potatoes everywhere to exercise and embrace nature.

Rachael Woodgate, 32, and Cressida Knapp, 21, came up with the idea for a competition at City College Brighton and Hove, where they study garden services.

Rachael said: "The theme was edible and decorative plants, which obviously includes potatoes.

"I wanted to play on the idea of the couch potato because there's been so much in news about how we are becoming fat and lazy."

The focal point of their garden, which will be on show at Hampton Court in July, is a full-sized grass couch. Opposite will be an old television transformed into a plant pot with a large pole and wires coming out of it.

Raised beds will include a number of potato varieties including bright red and blue ones and dozens of other unusual plants.

They include black tomatoes, rainbow chillies, a tobacco plant and a South American fruit shrub called Solanum quitoense which has not been seen at the show before.

Cressida said: "We wanted to mimic a living room with nature taking over."

The pair began sowing seeds and cultivating their grass couch in January and now have ten student volunteers to help preparations.

Cressida said: "The late spring and an attack of aphids worked against us but these plants have had a lot of tender loving care."

The college has won bronze and silver medals at the show but Rachael and Cressida hope to win its first gold.

Rachael said: "We are definitely going for gold."

Course leader Jim Miller said: "They have got potential. It's a very innovative and exciting garden."

Rachael and Cressida are looking for a sponsor. For more details, contact Jim Miller on 01273 601678 or email jm@ccb.ac.uk .