The Japanese 'U' flower [Deutzia scabra] is much like the common yellow flowering Deutzia in the Occident, except it is pristine white. It blooms in May and its green leaves appear to be covered in snow.
It is a a dark, warm, spring night and the poet is visiting a friend at twilight, just as the darkness of night begins. The gate to his cottage cannot be seen, but on both sides of it, flowers of the 'U' are blooming whitely. They are the only guide to where the gate stands, and where they suddenly leave off the gate must be. That will be a guide to his destination.
There is a very similar white flowering shrub here in Thailand, known as 'saniat moraa', though the habit of growth is not as pendulous, which I happened to encounter this morning. It was blooming as profusely as if it had been a cherished, well tended treasure in someone's garden. And yet it was growing amidst weeds in an empty lot. I went over to admire its magnificent show of flowers, and also to assure it that its lovely floral display was appreciated.






