Behind every true gardener’s eye lies a mirage of faraway China. So many of our best garden plants derive from Chinese parents. In the UK in June we are enjoying the generous white and pink-flowered deutzias and the profusion of pink tubular blooms on the excellent beauty bush, or kolkwitzia, an essential early shrub that has now reached an astonishing height of nearly 15ft in a sheltered part of my Oxford gardens. The spring gentians have been extra special and I have been appreciating the pink flowers on Clematis chrysocoma, which has been made so happy by the absence of cold English winters. All these plants and hundreds more are at home in China, where better forms of many of them have recently been discovered. I am not even bringing rhododendrons into the story – the reason why so many of the first western plant collectors were financed on trips to China in the previous century. The borderlands of China with Burma and Tibet have been holy homes of this supreme family of shrubs. Even the first professional collectors were astounded by their abundance and were often unable to collect more than a fraction of the natural riches that they encountered.

My mental image of it all is shaped by flowery descriptions, none flowerier than a sentence in which the collector and stylist Reginald Farrer described the local Tibetan poppy, meconopsis quintuplinervia, a plant I have seldom seen in a garden and never grown myself. “The senses ache,” he wrote, “at the multitudinous loveliness of its myriad dancing lavinder butterflies on the Alps of the Da Tung chain.” Often, in the season of our plain English buttercups, I recall these words and remember that there are even more amazing sights in lands to the east of us.