I’ve taken my cue from an erstwhile neighbour – Alfred Hitchcock was born just up the road in Leytonstone – and I’ve moved to the rear window. I’m in search of the colour purple. But instead of the lilac that coyly shows its first blush this time of year through the satin-white of the magnolia tree and the billowing chartreuse of the willow, I’m getting a Phoenician purple that would have turned Queen Elizabeth I, who banned the royal colour from her court, apoplectic.

This is the fourth in a series of articles written by London Blue Badge guides who used to be key workers in the capital. Janet Robinson writes about her work as a nurse before she became a London Blue Badge Tourist Guide.