The botanical gardens at Kew have hit back of allegations that its hugely popular Christmas event is a 'waste of money and energy'.

The annual Christmas at Kew showcase delivers a spectacular trail of light and video displays to add a festive explosion of colour to its fabulous grounds and buildings.

This year is the tenth annual show, which normally attracts thousands of people from across the borough and is a festive destination for visitors from across the country.

However, preparations have been over-shadowed by complaints from a few critics who argue it promotes waste and pollution, something vigorously denied by Kew Gardens.

This year's event is being marketed with a campaign boasting that it will feature designs containing more than one million lights. However, some environmentalists demanded to know more about its carbon footprint.

One critic, Nigel Witham, asked: "How is this wasteful, light-polluting, kitsch fantasia a good thing?

"Why don't you turn out your fairy lights and encourage us to look at the unviolated stars and contemplate our true place instead?"

He also suggested the light displays could displace wild birds.

Kew has made great efforts to find green power sources. This involves using LED lights and biofuel to run the generators which power the displays, which cuts emission by 90 per cent compared to diesel.

Biofuel is produced from by-product vegetable fats and oils, and is promoted as sustainable, low-carbon alternative to fossil fuels.

Kew responded to the criticism saying: "Consideration for the trail's sustainability is really important to us and we carefully consider this as part of the planning process.

"Our trail designers were appointed on the strength of their experience of working in environmentally sensitive ways in heritage and landscape settings.

"All Christmas at Kew generators run on HVO biofuel - a form of renewable diesel that has been produced from vegetable fats and oils.

"This results in up to 90 per cent reduction in greenhouse emissions.

"Finally, continuous lighting of trails and paths will be avoided, and we will only use audience area lighting where it is absolutely necessary for reasons of public safety."

A spokeswoman for the Royal Botanic Gardens said: "We are very aware of energy use and have made a conscious decision to continue the use of sustainable and efficient energy sources this year.

"We started trialling HVO biofuel generators in 2020 and have increased their use since.

"This year we are proud that all Christmas at Kew generators are being run on HVO biofuel and where we cannot use generators, we use mains power.

"Where possible all lighting, including up-lighting and path lighting, is LED.

"We are working hard to transition towards 100 per cent LED lighting for the artworks over the next couple of years. We are currently at 75 per cent LED.

"We have also designed the trail to avoid having continuous lighting of trails and paths and we only use audience area lighting where it is deemed absolutely necessary, for reasons of safety.

She added: "Royal Botanic Gardens, Kew, is a world-leading scientific organisation.

"We are critically dependent upon admissions revenue to both maintain the Gardens and to continue our vital scientific work in the conservation of rare species and in the preservation of threatened ecosystems throughout the world.

"Christmas at Kew was designed to attract visitors in the darker winter months by highlighting the beauty of the gardens in a unique and creative way.

"Each time we attract a new visitor, through our exhibitions, children's activities or evening events and trails, we introduce new audiences to the beauty of Kew's landscape and are able to continue our crucial work."

This year's event at the Royal Botanic Gardens, home to the largest plant collection in the world, marks the tenth year of the winter extravaganza.

It runs from November 16 to January 8. Entrance is £21.50 off peak and £28 at peak times.

https://www.kew.org/kew-gardens/whats-on/christmas