Grewia occidentalis (crossberry, "Suirenboku")

Japanese name: スイレンボク （睡蓮木）
Scientific name: Grewia occidentalis

[Overview]
In its native range, an evergreen shrub or woody climber about 2–4 m tall.
In dry areas it appears to be a much-branched shrub, and in forests it is vine-like, creeping on the ground or climbing on other objects.
It drops its leaves when exposed to low temperatures.
The leaves are simple and alternate, lanceolate to ovate, about 3–7 cm long, dark green and glossy.
The leaf margins have fine teeth.
The flowers are borne 1 to several in the leaf axils; they are 5-petaled and about 3–3.5 cm across, but because the inner side of the 5 sepals is the same color as the petals, they look like 10-petaled flowers.
The flower color is purple to pink, rarely white.
The petals and sepals are lanceolate, and the sepals are longer.
The outside of the sepals is tinged with green.
There are many stamens, and the anthers are yellow.
The fruit looks like 4 spheres joined together into a squarish shape, ripens reddish brown to reddish purple, and is edible.

[Cultivation]
Propagate by cuttings.
It prefers sun, good air circulation, and well-drained soil.
It can overwinter outdoors in regions without frost, but it is safer to bring it indoors to a sunny place in winter.
For potted plants, water thoroughly when the soil surface dries; for plants in the ground, rainfall is sufficient.
From spring to autumn, apply slow-release fertilizer placed on the soil.
There are no particular pests or diseases.

[Notes]
The name comes from the shape of the flower.

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