Prince Harry earned praise from his grandmother, Queen Elizabeth, on Monday – and both took time to smell the flowers.
“Well done,” she told him.
Harry, 30, and designer Matt Keightley spent five minutes with the Queen in the garden, which has an African-themed hut at its center.
“It was nice to be able to go from a sketch around a table with him and his father to revealing the finished garden,” Keightley tells PEOPLE. “He was really pleased with it.”
And in contrast to the earlier rain, Harry also switched gear. Gone was the fleece and on came a suit for his esteemed guests at the annual Chelsea Flower Show.
The Queen, who has been coming to the show, which traditionally kicks off England’s social season, for half a century, chose a royal blue coat by Karl Ludwig for the occasion.
“The relationship between grandson and grandparent and son and Prince Charles was clearly very close,” Philip Green, head of Sentebale, tells PEOPLE.
“Prince Harry was thrilled with the reaction he has received,” he added. “And when he described the garden as ‘perfect’ this morning, you know it is authentic. Harry speaks his mind, and if he didn’t mean it, he wouldn’t say it. He said, ‘I wouldn’t change anything.’ ”
There was another VIP visitor at the show – grandfather Prince Philip, 93. They greeted each other with a kiss on each cheek, and Philip welcomed Harry back from New Zealand.
The ‘Hope in Vulnerability’ garden is inspired by the charity’s Mamohato Children’s Centre, which will provide a safe and fun-filled place for children affected by HIV and AIDS to take part in residential camps.
Sentebale has recently passed its 10-year anniversary and was set up by Harry and Prince Seeiso of Lesotho to help young people affected by HIV and AIDS in the mountain kingdom in Southern Africa.
Keightley spent 18 days building the garden, but the planning began last June, and Keightley went out to Lesotho in August to gather inspiration for the visual concept and the flowers.
He thought he’d surprise Harry with a fun touch – some tiny footprints embedded in the stone pathway – to signify the children the charity helps.
“He liked the detail,” Keightley tells PEOPLE. “But he beat me to it as he said he had seen it on Twitter last night.”
Sentebale CEO Cathy Ferrier says she brought back prints of children’s feet from Lesotho for the stone pathway.
“The idea is children running through the garden, and Matt, who is great on detail, even got his nephew to pace them out, so he got the strides right,” she says.
The garden has a stone hut with columns at its center – a local touch imported from Lesotho.
“We have ‘knitted’ some native succulent plants – sempervivums and senecios – in there,” Keightley shared.
Ferrier also says the garden will help them publicize the soon-to-open children’s center.
“It will enable us to cater to 1,500 children a year, and will be the only purpose-built kids camp in Southern Africa. Children say they feel at home when they come to stay,” she says.
Keightley also told reporters: “Prince Harry has been intrigued by the correlation between the Chelsea garden and the children s center, so he was explaining to them which details would be taken out to the children s center.”
“Before they arrived, the prince was talking about the one Lesotho poppy that is flowering in the garden and joking about whether we should have offered it as a buttonhole,” Keightley shared.
He added that the royal family members wanted to know how many plants in the show garden are native to Lesotho, which is about 20 percent.
“The Queen really liked the color and vibrancy of the space,” Keightley added. “The Prince of Wales really liked the hurdle fence, which is made of peeled sweet chestnut.”
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