Rhododendron molle subsp. japonicum f. flavum ("Kirengetsutsuji")

Japanese name: キレンゲツツジ （黄蓮華躑躅）
Scientific name: Rhododendron molle subsp. japonicum f. flavum

[Overview]
A deciduous shrub 1–2 m tall, found at forest edges and in grasslands in the mountains.
Young branches have long hairs.
The leaves are simple, borne in threes in a whorl-like arrangement at the branch tips, oblong, 4–8 cm long and 1.5–3 cm wide, with stiff hairs on the margin, the upper surface and the veins of the underside.
The petiole is 0.1–0.3 cm long.
It flowers at the same time as the leaves unfold, and short racemes at the branch tips bear 2–8 flowers.
The flowers are yellow to yellowish orange, 5–6 cm across, and the corolla is funnel-shaped with 5 lobes.
The corolla has short hairs on both surfaces.
There are 5 stamens.
The fruit is a capsule with stiff hairs.

[Uses]
The leaves are used in folk practice as an insecticide and to kill maggots.

[Cultivation]
Propagate from seed.
Cuttings are also possible, although the rooting rate is very poor.
It prefers fertilized, acidic soil that is sunny, well drained and moisture-retentive.
Avoid dry sites, or prevent the base of the plant from drying out by mulching or similar means.
For potted plants, it is best to place them in partial shade out of the afternoon sun and direct summer sunlight from spring to autumn, and in a sunny spot protected from cold wind from autumn to spring; for plants in the ground, a site shaded by deciduous trees is best.
For potted plants, from autumn to spring water thoroughly when the soil surface dries, and in midsummer water twice, in the cooler morning and evening, so that the leaves are also wetted.
For plants in the ground, rainfall is sufficient except in summer; in summer, water in the cooler morning or evening so that the leaves are also wetted, and in winter, if dry weather continues, water in the morning on a warm day.
Apply fertilizer three times in total, in winter, after flowering, and in autumn, using organic fertilizer or slow-release chemical fertilizer with equal parts of the three components, spread around the plant.
Do not prune; limit work to rubbing off excess buds in early summer after flowering to tidy the shape of the tree.
Remove spent flowers promptly.
Pests and diseases include spider mites, Tsutsuji-gunbaimushi and Benimon-aoringa.

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