The re-opening of one of Kent’s most historic gardens has been scuppered on safety grounds after the owners were landed with a shock £500k bill.

The medieval Franciscan Gardens in Canterbury were due to welcome visitors back on June 10 after work to repair sections of a listed wall.

But a survey has now revealed further extensive structural issues with the ancient surrounding brickwork and two cottages in the 1.5 acre grounds, making it unsafe for the public.

It is a huge blow to the trustees who now urgently need to find substantial new funding for the additional works.

And the closure also means a loss of vital income from the thousands who would have visited.

The picturesque gardens in the heart of the city, which are the grounds to the historic Eastbridge Hospital, were originally created by Franciscan monks in the 13th century.

They are home to an exceptional display of ornamental flowers, medicinal plants, shrubs, and trees beside the River Stour, reflecting its long history from medieval to modern times

They have been described as Canterbury’s “best kept secret” and an “oasis of calm” away from the bustling High Street.

The trustees were forced to close the gardens on safety grounds when a section of river wall collapsed last October.

But heritage architects have now discovered far greater wide-spread structural issues with the walls and two cottages, with preliminary estimated repair costs of up to £500k.

“We are deeply saddened to have to keep the gardens closed until 2025 but have no choice,” says clerk and receiver to the Eastbridge Hospital, Louise Knight.

“We could have fenced off large areas but that would have ruined the visitor experience.

“It has put us in a horrible position because we have so much money to find.

“It is very specialist work because some of the walls have courses of brickwork three or four bricks deep.

“Of course, we will be making grant applications to organisations like the Heritage Lottery Fund, but we are among thousands of charities seeking funds.”

Mrs Knight says the Eastbridge Trustees have to remain “optimistic” they will get the money to do the work, which will allow the gardens to re-open in 2025.

“We want to maximise the visitor experience in this important historic site and oasis of calm in the heart of the city,” she says.

“Through the redevelopment of the buildings and grounds, our long-term aim is to illustrate the ways in which the history of the Franciscan Gardens is intertwined with that of Canterbury itself.”

The charity is already involved in the expensive restoration of the Eastbridge Hospital, which fronts onto the High Street and is also known as the Hospital of St Thomas the Martyr.

It was founded around 1180 to provide accommodation for poor pilgrims travelling to the tomb of St Thomas Beckett in Canterbury Cathedral.

It remains one of the city’s finest heritage assets as well as a destination for pilgrims to Canterbury and continues to provide almshouse accommodation.

It has an entrance hall and chantry chapel, a vaulted undercroft, the Juxton room – named after benefactor Archbishop William Juxton – and a refectory and pilgrims chapel.

But serious structural issues in a number of areas of the building – including the collapse of the refectory ceiling last year and the discovery of deathwatch beetle – forced its closure.

The gift shop, however, remains open.