Rhododendron ×mucronatum ("Ryukyutsutsuji")

Japanese name: リュウキュウツツジ （琉球躑躅）
Scientific name: Rhododendron ×mucronatum

[Overview]
A semi-evergreen shrub with spreading branches.
The leaves are simple and alternate, slender and densely hairy, with the margins slightly rolled toward the underside.
The flowers are usually large and white, the corolla is 5-lobed, and it flowers freely.

[History]
It is thought to be a hybrid of Kishi-tsutsuji and Mochi-tsutsuji.
It has been cultivated since the Edo period, and its name appears in Kinshu-makura (1692).

[Cultivation]
Propagate by cuttings.
It prefers well-drained acidic soil that retains water.
Avoid dry places, or prevent the base of the plant from drying out by mulching or similar.
Potted plants are best placed in partial shade out of strong afternoon sun and direct summer sunlight, and in a sunny place sheltered from cold wind from autumn to spring; in the ground, a spot shaded by deciduous trees is good.
For potted plants, water thoroughly when the soil surface dries from autumn to spring, and in midsummer water twice a day, in the cooler morning and evening.
For plants in the ground, rainfall is sufficient except in summer, when water in the cooler morning or evening.
Apply organic fertilizer or slow-release chemical fertilizer with equal amounts of the three components around the plant three times in total: in winter, as thanks fertilizer after flowering, and in autumn.
Pruning after summer would cut off the next year's flower buds, so prune as early as possible after flowering.
Remove spent flowers frequently.
Pests and diseases include aphids, scale insects, leafrollers, spider mites, azalea lace bugs and Hypocala moorei (Benimon-aoringa).

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