QBARS - v30n3 R. pentaphyllum var. nikoense

R. PENTAPHYLLUM VAR. NIKOENSE
Atsuya Hamada, Tochigi-Ken, Japan

A pure, albino-flowered form of Rhododendron pentaphyllum var. nikoense is pictured on the front cover. It is a tall shrub without lower branches which is the result of having grown in the wild for many years, struggling upward for more light, among other coarser shrubs and trees such as Quercus , Chamaecyparis and Clethra .

Beside this specimen, I have found six more albino-flowered forms of this species, all different. Some produce shallow saucer-shaped flowers, whereas other forms have deeper flowers. Although they are still on the shallow side, they are deep for this species.

The forms I prefer and consider the choicest have deep flowers with a clear yellow (usually faint) blotch, without any greenish tinge. The flowers are borne on short, robust stalks so that they do not hang down or nod with age, even in the rain.

Although the flowers look fragile, owing to their shy and naive appearance, they last for a week or so at least. Protection from violent spring storms at the flowering time is very beneficial in order to prevent the delicate flowers and twigs from rubbing against each other, which often results in stained and disfigured flowers. Careful selection of wind-free planting sites will allow the flowers to expand fully into a large mass of glistening white. The plant itself, however, is quite hardy and can tolerate a very cold exposed site easily, once it is established.

The seed distributed for the past two years under Hamada Cross No. 34 was a mixed batch of crosses between the five best albino-flowered forms available, Hamada 00036, 39, 40, 71 (pictured on the front cover), and 73. Every possible combination between any two of these was used, aimed at producing still more superior forms. For example, in making a cross between 39 and 40, 39 would be used as the pollen parent in the one cross and the seed parent in the next.