Gardeners fear they are to be turfed out of historic allotments in use for more than 100 years.

The Belmont Allotments, between Cotswold Road and Brighton Road, could be bulldozed to make way for the London Cancer Hub.

But one green-fingered pensioner, who himself was treated for prostate cancer in 2013, said that he would be “devastated” to lose the plots.

John Reeves, 74, said: “Working on the allotment, and eating the soft fruit that I produce, has been just as helpful as the treatment.

“It would be devastating for plot owners and everyone who holds the site dear if it was to be built on.”

Sutton Council is considering plans to integrate allotments and community gardens into the hub, a proposed world-leading research campus which is hoped to deliver two extra cancer drugs every five years and create more than 13,000 jobs.

A spokesman said the council had held talks with allotment users, adding: “The issue is whether we retain the allotments in their current location or move and even expand them onto a different part of the site in order to make space for the best design of new and enhanced cancer research facilities.”

But Mr Reeves, who has owned his plot since 2004, said relocating the allotments would mean “many hundreds” of hours spent improving and maintaining the site – including revamping its wildlife area last year – would be wasted.

He added: “Providing us with a building site covered in top soil just won’t do, and will make us have to start everything from scratch.”