Hydrangea quercifolia (oakleaf hydrangea, "Kashiwabaajisai")

Japanese name: カシワバアジサイ （柏葉紫陽花）
Scientific name: Hydrangea quercifolia

[Overview]
A deciduous shrub 1–2 m tall.
The leaves are opposite, ovate, about 8–25 cm long, and have 5–7 lobes.
The leaf margins are toothed.
The leaves turn red in autumn.
The flowers are borne in conical inflorescences 15–25 cm long, made up of white decorative flowers and bisexual flowers.
The fruit is a capsule.

[Cultivation]
Propagate by cuttings.
It prefers sun to partial shade and moist, well-drained soil that also retains water well.
It is not suited to places where the soil becomes extremely dry or where it receives strong afternoon sun.
It is easy to grow, vigorous, and flowers well every year.
It absorbs a lot of water, so for potted plants take care that it does not dry out, and water thoroughly when the soil surface dries.
For plants in the ground this is not particularly necessary, but during the high temperatures of summer, water in the morning or evening when the air is cooler.
Apply slow-release fertilizer twice a year: fertilizer in winter and fertilizer after flowering.
Flower buds form in the summer of the previous year, so if you prune, do so as early as possible after flowering.
When the plant has grown large and the branches are crowded, cut it back to near ground level to renew it.
Pests and diseases include leaf blight, powdery mildew, spider mites and aphids.

[Notes]
The Japanese name comes from the leaf shape resembling that of Akagashiwa.

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