Zanthoxylum beecheyanum var. alatum ("Hirezansho")

Japanese name: ヒレザンショウ （鰭山椒）
Scientific name: Zanthoxylum beecheyanum var. alatum

[Overview]
An evergreen shrub 0.5 m tall, growing on coral-reef limestone ground along the coast.
It branches freely and spreads by creeping sideways.
Small spines are sparsely arranged in opposite pairs on the branches, and young branches are at first covered with short hairs.
The leaves are alternate, odd-pinnately compound, 2–5 cm long, and consist of 7–13 leaflets; the leaf axis has broad wings.
The leaflets are rounded, with inconspicuous teeth or entire margins, and are hairless on both sides.
It is dioecious.
Both male and female flowers are borne in short panicles 1.5–2 cm long, and the flowers have 8 tepals with no distinction between sepals and petals.
The fruit consists of 1–2 segments, each one a green, bumpy sphere about 3 mm across.
When ripe, the fruit splits open to reveal black seeds.

[Uses]
The leaves and fruit are used in the same way as sansho, and are also used medicinally.

[Cultivation]
Propagate from seed or by cuttings.
Plants grown from seed will include both males and females.
It prefers sunny, well-ventilated, well-drained calcareous soil.
It tolerates partial shade.
It is vulnerable to cold, so in cold regions grow it in a pot and bring it indoors to a sunny spot in winter.
For potted plants, water thoroughly from spring to autumn when the soil surface dries, and keep it on the dry side in winter.
For plants in the ground, rainfall is sufficient unless sunny weather continues and the soil dries out.
Apply slow-release fertilizer from spring to autumn.
Pests and diseases include the larvae of swallowtail butterflies, aphids and leaf rollers.

View this page in Japanese (日本語)