Juniper

Regulation (EU) 2019/787 names juniper in every gin category. Juniper-flavoured spirit drinks may use Juniperus communis or J. oxicedrus, provided juniper remains discernible; gin and distilled gin must use J. communis, and juniper must be the predominant taste. The genever technical file allows both species and requires that other botanicals not dominate.

Jacob van Maerlant's Der naturen bloeme (c. 1266) recommends juniper boiled in rainwater or wine as a remedy. In 1757 the London distiller A. Cooper wrote that juniper berries were usually imported from Germany, though the shrub grew in England, and advised drying them thin on a boarded floor and storing them in closed casks.

A 2025 study at Heriot-Watt University distilled juniper from several countries and harvests. Growing region and drying both changed the levels of key terpenes such as α-pinene, β-pinene and β-myrcene in the distillate. The authors used Macedonian berries, from "one of the most established growing regions", as their benchmark, and note that much of the juniper used in the UK is harvested abroad and offered to distillers each November. Gin de Mahón's rules require berries dried for at least a year.