The Queen braved the rain

They were joined at the Chelsea Flower Show by the Earl and Countess of Wessex and other minor Royals.

It was Sophie's first official engagement since the countess and husband, Edward, announced she was pregnant earlier this month.

Celebrities from the worlds of sport and television were also among the visitors as the Royal Horticultural Society's (RHS) 81st annual show opened for previews at the Royal Hospital in Chelsea, west London.

Olympic legend Sir Steve Redgrave, Cilla Black and former Arsenal player Frank McLintock were among those admiring the displays.

Ringo Starr and his wife were among guests at the opening

The FA Cup has been recreated using flowers and former Beatle Ringo Starr was opening an 'octopus garden', to show his support for coral reef conservation.

The Soham Rose, dedicated to Holly Wells and Jessica Chapman who were killed in Soham, Cambridgeshire, was also unveiled.

Representatives of Soham Town Council received the rose, proceeds from its sale will go towards the Holly and Jessica appeal fund.

The idea of dedicating a rose to the girls' memory came after Holly's father, Kevin, wrote a poem called Soham's Rose, which he read out at their memorial service.

The creators, businesswomen Nadine Smith and Coral Paxton and solicitor John Aspinall, from Soham, said: "The immediate aim is to raise money to serve local community needs in ways which recognise the tragedy of what has happened."

Originally called the Great Spring Show First held in Kensington in 1862 600 exhibitors 60 gardens Exhibits are judged by RHS before the show opens

The Queen visited a garden by staff and inmates at Leyhill Prison, Gloucestershire.

Jez, who is coming to the end of a six-year sentence, told her he had taken up gardening in jail and wanted to pursue it professionally on his release.

Daisy Rogers, nine, presented the Queen with a posy at Sunflower Street, a garden sponsored by The Sun newspaper.

There are more than 60 gardens for visitors to inspect and there are 600 exhibitors from South Africa to Jamaica taking part.

Environmentally friendly gardening is a major theme this year, with ideas ranging from naturalistic planting to the more adventurous planting roof spaces, effective for insulation and absorbing noise and pollution, from Help The Aged.

A visitor admires the new Soham rose at the Chelsea show

The RHS say a noticeable trend this year is a move towards greater geometry or symmetry in garden design.

The ubiquitous water feature is well represented, with a water umbrella, the octopus garden and a clock that drips instead of ticks.

There is an artificial pond with a plasma screen showing images of koi carp, while another features a patio filled with bubbles.