Prince William and Kate make Chelsea Flower Show debut alongside Harry and the Queen

The opening day of the Chelsea Flower Show brought members of the royal family out in full force on Monday (May 23). It was a first for the Duke and Duchess of Cambridge, who joined regulars like Prince Harry, the Queen and Her Majesty's daughter Princess Anne as they made their debut at the horticultural event.

The Queen's son Prince Andrew and his daughters Princesses Beatrice and Eugenie were also spotted arriving.

William and Kate, who have never visited as a couple, made a very sunny appearance. The Duchess, 34, opted for a bright and summery look, wearing a recycled green Catherine Walker coat dress.

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The pair, alongside Harry, toured the different exhibits, which were organized under this year's theme of Health, Happiness and Horticulture. They also admired the special arch that was erected to celebrate the Queen's 90th birthday and the breathtaking sea of hundreds of thousands of poppies in the grounds of the Royal Hospital Chelsea.

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The highlight of William and Kate's visit will have been viewing a new flower that has been named after their daughter Princess Charlotte. The Princess Charlotte chrysanthemum, which is pink with green tips and is known as the Rossano Charlotte, is being entered in the Flower of the Year category.

It has been produced by Dutch company Deliflor, the world's largest chrysanthemum breeder, which previously delivered a bouquet of flowers to William and Kate following the birth of their daughter last year.

The Queen is patron of the event, which runs from May 24 to 28. Her Majesty and Prince Harry are regular fixtures at the annual flower show. Harry, 31, has previously visited to view a garden created in honour of his charity Sentebale, which supports children suffering with HIV/AIDS in Lesotho.

Prince Edward's wife, the Countess of Wessex, also attended the opening day, which is typically reserved for royals and celebrity guests. Sophie was her usual stylish self in a floral Alexander McQueen dress and black cropped jacket.

A host of stars descended on the gardens including Demi Moore, Rosamund Pike and Mary Berry, who inspected a new rose that has been named after her.

Presenter and gardener Alan Titchmarsh chatted to fans at the event, while Dame Judi Dench, Naomie Harris, Jerry Hall and Rupert Murdoch and Tracy Chevalier were also spotted among the sea of guests.

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