Hanyuan or Sichuan pepper is in reality a perennial and spiny plant that does not belong to the Piper but rather the Zanthoxylum variety (Rutaceae family). Many of the 250 species of Zanthoxylum produce berries that are collected and harvested just like common pepper (Piper nigrum) and used for the same purpose.
It has been collected for more than a thousand years in China in the Sichuan and was once offered as a gift during religious ceremonies under the name Lijiao.
The berries are rather large, rounded and dark red. The aroma is intense and similar to that of pepper and it is particularly used to flavour warm dishes.
The plants reproduce via seeds and start to produce berries after 3 years. They have reached their peak after 5-6 years and continue to fruit for around 50 years. They germinate in March and harvest takes place in July until the end of October. After harvest the berries are left to dry in the sun that is very hot in the County of Hanyuan. It takes only one day for the berries to dry and then they are stored or prepared for sale.
Cultivation in Zanthoxylum dates back to more than 350 years ago. When Emperor Han Wudi occupied Xinanyi in the sixth year of the Yuanding period, the Zanthoxylum was already a local speciality of Hanyuan.
From the Yuanhe period of the T’ang dynasty, the Zanthoxylum from Hanyuan was considered a tribute and used as an ingredient and for medicinal purposes. As noted in the Annals of the County of Hanyuan, ""the Zanthoxylum of Hanyuan has a delicate aroma and can be used readily, it is known as a local speciality and offered as a tribute … all the governors possess a bag of Zanthoxylum from Hanyuan to conserve, whoever receives Zanthoxylum, receives a precious gift"".
Eating a small quanity of Zanthoxylum serves to lower qi (vital energy in Chinese medicine) when one is unwell and parents may give it to lively children to calm them down.
Production of Zanthoxylum in the County of Hanyuan is now reduced because of climatic change, the lower profit involved compared to fruit growing and also because of the great work involved in its preparation. There are many false Sichuan peppers on the market, creating great confusion.