Zanthoxylum schinifolium

The Zanthoxylum schinifolium, sometimes called the Sansho pepper bush, is part of a group of small Asian trees called pepper bushes, known for their aromatic fruits used in cooking as Sichuan pepper. This Korean and Japanese species, schinifolium, is traditionally cultivated in Japan for the skin of its berries, which have fresh citrus and lemongrass aromas and give remarkable flavours to local cuisine. This pepper bush is also attractive for its easy cultivation, its beautiful finely cut foliage, and its peculiar rough bark on old specimens. Small berries follow discreet summer flowers, the dried and ground husk used as a spice. It finds its place in a free hedge, and its thorny young branches work wonders in a defensive hedge. For this reason, it is best to place it far from a walkway and wear gloves for harvesting!

Native to eastern China, Korea, and Japan, the Zanthoxylum schinifolium belongs to the same family as citrus trees, the Rutaceae family, with which it shares a very aromatic foliage. It loses its leaves in winter, tolerates occasional temperatures down to -18°C, and grows in any well-drained and sufficiently deep soil. However, young plants are more sensitive to cold. 

This small tree, which grows rapidly in fresh and fertile soil, measures an average of 3.50 m (11ft) in height with a spread of about 3 m (10ft) at maturity. It has a graceful, naturally spreading habit supported by flexible branches. This species develops one or more trunks topped with a rounded, semi-open crown. The trunk and branches are adorned with strong thorns that widen and flatten significantly over the years while their tips become blunt. The branches bear deciduous leaves arranged alternately, divided into 11 to 21-toothed leaflets, producing essential oils and fine prickles. When crushed, they release a lemony and slightly peppery scent. Their colour is a beautiful dark green, turning yellow in autumn before falling off. Flowering occurs in July-August, depending on the climate, on one-year-old branches. It consists of small compact clusters or cymes composed of small flowers with a brownish-green colour. This shrub has both male and female flowers. After pollination, slightly flattened fruits, 3 to 4 mm (1in) in diameter, form on the female flowers. The fruit is green when ripe, opening to reveal black and shiny seeds. Only the husk is consumed once dried and ground. Since ancient times, Sansho pepper has been used as a natural preservative for meat and fish. 

In the kitchen:

The berries of this Sansho pepper bush should not be confused with "pink berries" or "pink pepper" sold in the spice section: the latter are produced by another small tree called Schinus terebinthifolius, the Brazilian pepper tree, native to South America. In cooking, we will use the green "skin" of the fruits of our Zanthoxylum to enhance preserves, rice, salads, and cooked dishes. This spice is essential in traditional Asian cuisine. The dried and powdered leaves are also used, especially in Japan: their aroma is very similar to that of the berries.

In the garden:

This unusual small tree has its charm in an English or naturalistic garden. If you plant this on its own, it can look stunning and surprise your guests. To show off its trunk, trim the lowest branches up to 1 metre (3 feet) from the ground. Left untrimmed, it naturally finds its place in an untrimmed hedge alongside dogwoods, rowans, viburnums, Osage orange, apple trees, and ornamental cherries, bee trees, for example. The thorny nature of its young branches makes this beautiful shrub an ideal candidate for a defensive hedge. Pair it with Poncirus trifoliata, Rosa moyesii, Pyracantha, hawthorn, Japanese quince Cido, or sea buckthorn.