It’s hydrangea season, and practically every suburban garden worth its name has a bush covered in big pink pompoms. Along with roses, it’s the flower of the English summer. Down at Kew Gardens they have a different approach. Their hydrangeas grow in secret, tucked away beneath the trees in the woodland glade. You have to seek them out, but at this time of year it’s worth the effort.

There are two kinds of hydrangeas. The ones you see most in people’s gardens are mopheads, with large round flower heads like pompoms or, as the name says, the head of a mop.

Down at Kew they’ve gone mainly for the other sort, lacecaps, with round, flat flower heads with a centre of little fertile flowers surrounded by an outer ring of showy, sterile flowers.

Hydrangeas actually originate in eastern Asia, mainly China, Japan, and Korea. In Japan they flower in the rainy season in June, the one time of year that satisfies their insatiable desire for water.

if you want to find the hydrangeas at Kew, head for the Chinese pagoda and find a broad green path stretching down towards the river. About half way down the path you’ll see a splash of colour under the trees – that’s them.