The Duke of Edinburgh joked with his wife as he planted a tree in a Nepali garden, next to two that were planted by his parents almost 40 years ago.
Edward and Sophie toured the Godawari National Botanic Garden on the second day of their official royal tour of the Himalayan nation.
The couple held hands as they walked down a flight of stone stairs after visiting the site’s orchid house, with views over the Kathmandu Valley.
Earlier, they joked together while planting a magnolia tree, metres away from a pair planted by the late Queen and Duke of Edinburgh in 1986.
The duke said: “Gosh they’ve done very, very well,” as he was shown the trees from his parents’ previous visit.
The duchess encouraged her husband as he picked up a spade and filled in the hole for the new tree, saying: “Keep going, darling.”
The pair both laughed as Edward said: “That’s the best bit of exercise I’ve had in ages.”
They then took it in turns to water the tree, with the duchess saying: “This is going to make all the difference,” as she picked up the watering can.
Sophie later planted a rhododendron with some local children, asking them to look after it for her.
The duchess expressed concern about the amount of waste left by climbers on Nepal’s most famous landmark, Mount Everest, during the couple’s second engagement of the day at the International Centre for Integrated Mountain Development’s (ICIMOD) Living Mountain Lab.
Sophie asked if any of the money paid by people to climb the mountain was “being earmarked for dealing with some of the issues”, saying: “People leave everything behind and it has a huge impact.”
After being told that the average traveller on Everest produces eight kilos of waste, and many would rather pay a government fine than take it with them, the duke said: “It’s difficult because you have to come down very quickly to make room for those coming up so you try to leave as much behind as possible.”
Sophie replied: “But they don’t collect it on the way down again.”
The duchess went on to say: “It’s a very visible manifestation of human impact, isn’t it?”
As they toured the site the royals heard about the climate challenges facing Nepal and the Hindu Kush Himalaya.
ICIMOD scientists showed the couple how they are developing technologies for climate-resilient agriculture, sustainable land and water that can be applied in the region.
The duke and duchess also met the seven finalists of the UK-funded Hindu Kush Himalaya Innovation Challenge for Entrepreneurs.
Later, the duke and duchess flew to the lakeside city of Pokhara and visited the Gurkha Welfare Trust’s welfare centre, where they met elderly veterans and widows supported by the charity.
Among them was 104-year-old resident Ash Kamari Tamang, who moved to the centre in 2011 after the trust stepped in when she was struggling to care for herself.
Her husband enlisted in 1943 and served in Italy before his battalion was disbanded in 1945, and he returned to Nepal and became a farmer. The trust provided him with a pension until died in 2006.
The duke asked if the centre was looking after her well, to which she responded: “They must be doing a very good job.”
The royal couple also spoke to 99-year-old Burma war veteran Bar Bahadur Gurung, who suffered a debilitating hand injury when a Japanese soldier cut his finger with a sword.
After hearing his story, the duke told Mr Gurung: “Thank you for what you did. We appreciate it.”
After a group photograph, Edward said to the veterans and widows who had gathered: “Thank you for what you and your husbands did.”
He added, speaking to the charity’s staff: “And thank you for everything that you do.”
