Perennial with a deep tap root, leaves up to 20 in (50 cm) long, and clusters of 4-petaled white flowers.
Habitat & Cultivation
Native to Europe and western Asia, this herb is widely cultivated for its root, unearthed in autumn.
Horseradish root contains glucosilinates (mainly sinigrin), flavonoids, asparagine, resin, and vitamin C. On being crushed, sinigrin produces allyl isothiocyanate, an antibiotic substance. The flavonoids have been shown to be antioxidant.
History & Folklore
Pliny (23–79 CE) probably had horseradish in mind when describing a plant that warded off scorpions, but for most of its long history, horseradish has been used mainly as a diuretic herb. It is a popular condiment, particularly in Britain and central Europe.
Medicinal Actions & Uses
Now undervalued as a medicinal herb, horseradish has many healing properties. It strongly stimulates digestion, increasing gastric secretions and appetite. It is a good diuretic and promotes perspiration, making it useful in fevers, colds, and flu. It is also expectorant and mildly antibiotic, and can be of use in both respiratory and urinary tract infections. A sandwich of freshly grated root is a home remedy for hay fever. Externally, a poultice of the root can soothe chilblains.
Over-consumption of horseradish may irritate the gastrointestinal tract. The plant should be avoided by those with low thyroid function. A horseradish poultice may cause blistering.