The Royal Botanic Gardens is turning to the public to help rescue Kew’s historic Palm House, which is showing serious signs of deterioration.

A £66 million makeover is needed to save the Victorian building, with about half of that total already secured from philanthropists, grants and individuals.

A fundraising appeal has now been launched in hopes of raising a further £1 million.

The glasshouse has stood at the heart of the west London gardens since the 1840s. It is one of the world's most famous glasshouses and since 1775 has been home to the oldest pot plant in the world.

Inside, visitors can experience parts of a tropical rainforest in London, among an internationally significant collection of plants from around the world.

The plants behind its glass walls include species that are rare, threatened and even extinct in the wild, alongside others important to human life, such as coffee, rattan palm, banana, Madagascan periwinkle and the neem tree.

The collection also underpins Kew's research into preventing biodiversity loss, conservation and food security, as well as novel ways to protect the planet's future.

Richard Deverell, director of Royal Botanic Gardens, Kew said: “For generations, the Palm House has been a place where people encounter the extraordinary diversity of life on Earth.

“It is a building that has inspired wonder for almost 180 years, but its future cannot be taken for granted.

“Every donation, however large or small, will help protect this extraordinary building and the collection within it for generations to come.”

Members of the public can support the renovation by making a direct donation, sponsoring a pane of glass, or sponsoring a tropical plant species, such as Caly's hibiscus or the giant dioon.

Donations up to £300,000 will be matched, the gardens said.

The Palm House will close in February as teams carry out the final phase of removing plants, before reopening in summer so visitors can see it empty.

In autumn 2027, the building will shut its doors for the renovation itself, with works estimated to take between three to four years.

The improvements will include new glazing, a move to renewable heating systems and the integration of rainwater harvesting tanks.

Kew is aiming to create the first carbon neutral glasshouse of its kind.

Officials hope the work will conserve and future-proof the building for the 21st century while safeguarding thousands of tropical plants.

Dame Judi Dench, Palm House appeal ambassador, called it “one of Britain’s most iconic buildings – a place of beauty, discovery and hope”.

“By supporting its renovation, you will be making an investment in both our heritage and our future,” she added.