Hydrangea febrifuga (Chinese quinine, "Jozan'ajisai")

Japanese name: ジョウザンアジサイ （常山紫陽花）
Scientific name: Hydrangea febrifuga

[Overview]
An evergreen shrub 1–2 m tall, growing in mixed forests on mountain slopes and along valleys in its native range.
It has a rounded habit.
The leaves are simple and opposite, obovate to lanceolate, 6–25 cm long and 2–10 cm wide, with pointed tips and glossy upper surfaces.
The leaf margins are serrate.
Corymb-like panicles at the branch tips bear no ornamental (sterile) flowers.
The flowers are 5-petaled and open in a star shape; the outside of the petals is white to pale blue and the inside is deep blue, so the inflorescence looks two-colored.
The petals are oblong with pointed tips and thick in texture, and curl back as the flowers open further.
The buds are round and white to pale blue.
Flower color is affected by soil acidity: deep blue in acidic soil, and lilac or pale blue in alkaline soil.
The fruit is a spherical to elliptical berry 0.3–0.7 cm in diameter, ripening to a glossy deep blue (gentian blue).

[Uses]
It is used medicinally.

[Cultivation]
Propagate from seed or by cuttings.
It prefers moist, well-drained soil that retains water, in sun to partial shade.
It is somewhat tender to cold, so in regions with frost bring it indoors in winter to a sunny, warm place.
It is unsuitable for places where the soil becomes extremely dry or that receive strong afternoon sun.
Take care that it does not run short of water; for potted plants and plants in the ground for less than 2 years, water thoroughly when the soil surface dries.
Plants in the ground that have taken root need no special watering, but if the soil dries out during the hot summer, water in the cooler morning or evening.
In addition to base fertilizer, apply organic fertilizer in winter and as thanks fertilizer after flowering.
The flower buds for the next year form in autumn, so prune immediately after flowering, only tidying the branches that have grown long.
There are no particular pests or diseases.

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