Zanthoxylum simulans, also known as Sichuan pepper or Chinese pepper tree, is a striking yet relatively unknown large shrub or small tree. Originally from Sichuan, China, it has long been valued for its culinary uses. However, it also thrives well in the Northern European climate. Its ornamental value lies not only in the red pepper-like seeds, but also in its irregular growth form, attractive compound leaves, and beautiful autumn color. In this article, we highlight the valuable qualities of this plant.
Zanthoxylum simulans naturally occurs in eastern China and parts of Taiwan, where it can be found across different regions. Of the more than 250 known species, most Zanthoxylum grow in (sub-)tropical climates, with around ten species suitable for Northern Europe. The plant belongs to the Rutaceae family, which also includes the entire citrus genus, as well as Tetradium, Phellodendron, and Ptelea. The name Zanthoxylum refers to the yellow heartwood found in some species (xanthos means yellow and xylon means wood in Ancient Greek). Its historical use goes back centuries, with evidence that it has been cultivated and consumed for over a thousand years.
In ancient China, Sichuan pepper was highly prized for both its culinary and medicinal properties. The name “Sichuan pepper” itself reflects its deep connection with Sichuan province, where it is still widely cultivated.
A Distinctive Plant
What sets Zanthoxylum simulans apart from many other plants is that it is essentially a spice. The seeds’ unique flavor profile, combined with their distinctive tingling sensation in the mouth, makes them remarkable. The seeds are rich in oils containing a compound called sanshool, which is responsible for both the numbing effect and the tingling, citrus-like taste.
Functional and Ornamental
Zanthoxylum simulans is easy to grow, requires little from the soil, is disease-resistant, and very hardy. In spring, it produces tiny, almost unnoticeable flowers in clusters. By July and August, these develop into small red fruits, the so-called peppers. Its attractive compound leaves resemble those of the manna ash (Fraxinus ornus), but are more delicate in every detail. During flowering, bees, hoverflies, and butterflies find nectar in the blooms. Thanks to its dense growth and large thorns, the plant provides excellent shelter for birds, which also relish its berries.
In autumn, the fragrant foliage turns a striking yellow-orange. In winter, its irregular branching and prominent thorns create a striking silhouette. This large shrub is a fine addition to parks and gardens, and it can also be grown in containers or even on rooftop gardens, provided it is sheltered from strong winds. Thanks to its considerable ornamental value, Zanthoxylum simulans deserves a solitary spot in landscape designs, well beyond its place in food forests.
