Rhododendron indicum

Japanese name: サツキ（野生種） （皐月）
Scientific name: Rhododendron indicum

[Overview]
A semi-evergreen shrub 0.5–1 m tall, found on rocky ground along riverbanks.
Young branches and petioles have pale brown stiff hairs.
The leaves are simple and alternate, lanceolate, 1–3 cm long and 0.4–1 cm wide.
Pale brown stiff hairs grow sparsely on the upper surface, the margin, and the veins of the underside of the leaf.
The petiole is 0.1–0.2 cm.
There are 1–2 flowers at the branch tips.
The flowers are vermilion and 3–4 cm across, with a funnel-shaped corolla that is 5-lobed.
There are dark spots on the inner surface of the upper side of the corolla.
There are 5 stamens.
The calyx is densely covered with long hairs.
The flower stalks are densely covered with brown stiff hairs.
The fruit is an oblong capsule densely covered with stiff hairs.

[Cultivation]
Propagate from seed or by cuttings.
It prefers fertile, acidic soil that is sunny, well drained and moisture-retentive.
Avoid dry sites, or mulch to keep the base of the plant from drying out.
For potted plants, it is best placed from spring to autumn in partial shade out of the afternoon sun and direct summer sunlight, and from autumn to spring in a sunny spot protected from cold wind; in the ground, a spot in the shade of 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 cool of morning and evening, wetting the leaves as well.
For plants in the ground, rainfall is sufficient except in summer; in summer, water in the cool of morning or evening so that the leaves are wetted too, 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 as thanks fertilizer, and in autumn, using organic fertilizer or a slow-release chemical fertilizer with equal amounts of the three main components, around the plant.
Remove spent flowers promptly.
Pests and diseases include brown spot, spider mites, azalea lace bugs and Hypomecis-type moths (Benimon-aoringa).

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