In the Japanese art of flower arrangement, ikebana, there is usually acontrived asymmetry in the way the flowers and plants are combined. This is
said to reflect the irregularities in nature itself. Such an asymmetry
of arrangement was in this clutch of Morning Glories 'in the wild', as
it were. Or perhaps it was this photographer, seeking or making such
asymmetry, a kind of photographic ikebana...
Whatever... This kind of Ipomoea nil (as it is called now, but not without long discussions and much controversy) is the much-beloved 'asagao' of the Japanese. Since it was imported here from China in the tenth century, it is everyone's favorite, poets', of course, but also that of children. Often they are taught the first elements of gardening from this plant.
The European naturalist and 'observer' of Japan, Engelbert Kaempfer (1651-1716), doctor of the Dutch trading post at Dejima, is the first European to make note of it and its Japanese name, which he renders as 'asagawo'. I've checked Carolus Linnaeus, but though he quotes Kaempfer elsewhere, he doesn't for what he calls 'Convolvulus nil'. There's still a lot to be sorted out in the historical taxonomy of Our Blue.
Much-beloved of poets, indeed. I can't but repeat - I know no Japanese - a little gem (found on the internet) by the great Bashô (1644-1694):
ware wa meshi kû
This was translated by that lover and admirer of Japan, Reginald Horace Blyth (1898-1964) as:
'I am one
Who eats his breakfast,
Gazing at morning glories.'
Whether the Lords of the Castle of Matsuyama, the Matsudairas, did so at Ninomaru - where I saw these Glorious Flowers - I don't know. But I sure would have... Just look at the way the sunlight has caught the purple-pink throats.