Rupert Murdoch and new wife Jerry Hall paid tribute to soldiers from his native Australia who died during the First World War, as they visited the Chelsea Flower Show.
The media mogul and his model wife looked solemn as they admired the sea of 26,000 crocheted poppies installed in front of the Royal Hospital in a exhibition curated by Phillip Johnson, winner of Best Show Garden in 2013.
Hall embraced the floral theme in a cream dress with poppy and daisy pattern, while Murdoch kept his cool in a dark suit and white Panama hat.
The exhibit grew out of the 5,000 Poppies Project, established to celebrate the sacrifice of Australian and New Zealand servicemen, which was flown to the UK to create the breathtaking carpet of flowers outside the Royal Hospital, home of the Chelsea Pensioners.
Celebrities flocked to the flower show to spend a day in the sunshine admiring exhibits including a Belmond British Pullman train carriage as part of a 6,000 sq ft planted-up station in the Grand Pavilion, an acoustic garden inspired by world-leading percussionist Dame Evelyn Glennie which plays musical notes to visitors, and a garden of bizarre gadgetry by Diarmuid Gavin, which comes to life every 15 minutes.
Great British Bake Off star Mary Berry, who helped fashion chain Zara sell out of a floral bomber jacket when she wore it on the show, shunned foliage for a bright turquoise outfit.
The baker happily posed with the new Harkness rose which has been named after her.
David Walliams, who was joined by his mother Kathleen, joked he had made a wrong turn on the way to Chelsea's football stadium as he wandered among the gardens.
Naomie Harris, who plays Miss Moneypenny in the Bond franchise, looked summery in a crisp white suit.
Others in attendance included Downton star Jim Carter, celebrity gardeners Alan Titchmarsh and Gavin, adventurer Ben Fogle and presenter Gaby Roslin.
Members of the Royal Family, including the Queen, will take a tour of the show in the afternoon.
The RHS show at the Royal Hospital will be open to the public from Tuesday, with 160,000 people expected through the gates during the week.
Actress Rosamund Pike showed off her green fingers as she helped celebrate the 150th anniversary of children's charity Barnardo's.
The Gone Girl star laughed as she pretended to pour water over two "blooming" four-year-old helpers posing in a large bucket, both of whom are supported by the charity's The Triangle centre in Crystal Palace, London.
Pike, renowned for her English rose looks, introduced the new Syrie Rose, from Harkness Roses - named after the wife of founder Thomas Barnardo.
The mother-of-two spoke about her experiences of parenthood and said it was a "wrench" to be separated from sons Solo, four, and Atom, one.
She said it was "shocking" that only 14% of women in the film industry have children but added that if her partner, Robie Uniacke, had not been able to travel with her on location she would have had to rethink her career.
She said: "It's not easy being an actress and a mother but it happens to any working woman that career and motherhood come at the same time.
"I'm very lucky that my other half is self-employed and we can all go as a family. I'd have to rethink my whole job if that wasn't the case."
Pike, who played Bond girl Miranda Frost in Die Another Day, refused to be drawn on who the next 007 could be.
"I can't!" she said. "Good luck to whoever gets it because it's a wonderful gig."
Mary Berry chose not to sugarcoat her words as she predicted a batch of baking disasters for this year's The Great British Bake Off contestants.
The 81-year-old judge is currently filming the upcoming seventh series alongside Paul Hollywood, Sue Perkins and Mel Giedroyc, which is due to air in August, and said it was plain sailing so far.
She teased: "They're all doing very well but there's plenty of time for disasters to come."
National treasure Berry was at the Chelsea Flower Show to reveal the new Harkness Rose named after her.
She said she was "honoured" to have given her name to the Mary Berry Rose, a hybrid tea rose bred from her favourite variety Chandos Beauty, which has taken seven years to cultivate.
She admitted that she does not use rose often in her recipes and that she was a "fair-weather gardener" herself, but that she can not wait to see the roses in the "wonderful" garden of the home she shares with husband Paul in Buckinghamshire.