Rhododendron yedoense f. yedoense ("Yodogawatsutsuji")

Japanese name: ヨドガワツツジ （淀川躑躅）
Scientific name: Rhododendron yedoense f. yedoense

[Overview]
A cultivar of Chosen-yamatsutsuji, a deciduous shrub 1–2 m tall.
Young branches and leaf stalks are densely covered with pale brown bristles.
The leaves are simple and alternate, clustered at the branch tips, slender oblong, 4–7 cm long and 0.8–2 cm wide, with slightly pointed tips and long white hairs on both surfaces and the margins.
The scales of the flower buds have glands and are sticky.
It flowers at almost the same time as the leaves open, with 2–3 flowers at the branch tips.
The flowers are reddish purple, 5–6 cm across, and double, peony-type.

[Cultivation]
Propagate by cuttings.
It prefers sunny, well-drained, fertile 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 from spring to autumn in partial shade out of afternoon sun and direct summer sunlight, and from autumn to spring in a sunny place sheltered from cold wind; 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, wetting the leaves as well.
For plants in the ground, rainfall is sufficient except in summer, when water in the cooler morning or evening, wetting the leaves as well; in winter, if dry weather continues, water in the morning of a warm day.
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.
Do not prune; just thin the buds in early summer after flowering to tidy the shape.
Remove spent flowers frequently.
Pests include spider mites, azalea lace bugs and Hypocala moorei (Benimon-aoringa).

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