Rhododendron pentaphyllum var. shikokianum ("Akebonotsutsuji")

Japanese name: アケボノツツジ （曙躑躅）
Scientific name: Rhododendron pentaphyllum var. shikokianum

[Overview]
A deciduous shrub 2–4 m tall, found on rocky ground in deep mountains.
Young branches are hairless and reddish brown.
The leaves are simple, borne 5 at a time in a whorl-like arrangement at the branch tips, elliptic, 2–5 cm long and 1.5–3 cm wide, with short hairs on the midrib of the upper surface and dense short white soft hairs on both sides of the midrib on the underside.
The leaf margin has long hairs.
The petiole is 0.3–0.5 cm long, with long hairs and glandular hairs.
It flowers before the leaves unfold, with one flower at each branch tip.
The flowers are pale reddish purple, 5–6 cm across, and the corolla is 5-lobed and opens like a saucer.
The tips of the corolla lobes are shallowly 2-lobed or notched.
There are 10 stamens; the upper 5 are short, with dense short white hairs on the lower half of the filaments, and the lower 5 are long and almost hairless.
The fruit is a cylindrical capsule and is hairless.

[Cultivation]
Propagate from seed.
The rooting rate is poor, but cuttings are also possible.
It prefers fertile acidic soil that is sunny, well drained and retains water well.
Avoid dry sites, or prevent the base of the plant from drying out by mulching or similar means.
It is best planted in a place shaded by deciduous trees.
Except in summer, rainfall is sufficient; in summer, water in the cool morning or evening so that the leaves are also wetted, and in winter, if dry weather continues, water in the morning of a warm day.
Apply fertilizer three times in total: fertilizer in winter, fertilizer after flowering as thanks to the plant, and in autumn, placing organic fertilizer or slow-release chemical fertilizer with equal amounts of the three components around the plant.
Do not prune; at most, thin the buds in early summer after flowering to tidy the shape.
Remove spent flowers frequently.

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