One finds useful information in the oddest places. A few months ago, I chanced across
a very interesting blog by a British expat who lives in Tokyo.
In
one of his most recent postings, he describes a trip to
in which he mentions being able to discern in the distance
, "one of the wettest places on earth".
As readers are probably aware, Yakushima Island is home to any number of highly desirable dwarf forms of good plants, among them
Rhododendron keiskei var. cordifolia (perhaps most familiar as the cultivar 'Yaku Fairy') and
Viola verecunda var. yakushimana. I have found the latter very tricky to grow, at least to keep going from year to year. While it is fully hardy (my plants originated in the cold climate of Ithaca, New York), it appears to be touchy about drainage and the amount of water it gets. The best results so far have been in my panacea for tricky plants, volcanic pumice, but winter watering has posed a problem. In the past I have kept my potted plant(s) fairly dry in winter, but now I think that it probably needs reasonable watering even during winter - though not
the unending wetness of the Yakushima summer.
So perhaps
V. yakushimana, as it is familiarly known to its friends, will do better for me in coming years.
The same blog describes a trip to
. In passing, the inhabitants' defenses against the fierce winters, snowy, cold, and extremely windy, are mentioned, including pictures of snow barriers. This has clued me in to the ecological requirements of
Pteridophyllum racemosum, another choice plant from Japan which I have difficulty keeping going. Clearly it needs considerable water during the summer, and in winter should be kept as cold as possible, but also not allowed to dry out.
Thus, it pays to browse the web widely: you never know where you will find clues to the successful cultivation of tricky plants.