Designed for the Prince Regent by the architect John Nash, Regent's Park is noted for its lovingly tended blooms. But soon the flower beds of that - and other London royal parks - could make way for rows of humble carrots, cabbages and globe artichokes.

In a plan inspired by American cities, the royal parks are pondering the creation of a string of model allotments to give the public a living, ripening illustration of the virtues of growing your own fruit and vegetables.