to its medicinal uses, he says: Etymology and common names The word horseradish is attested in English from the 1590s. It combines the word horse (formerly used in a figurative sense to mean strong or coarse) and the word radish. In Central and Eastern Europe, horseradish is called khren, hren and ren (in various spellings like kren) in many Slavic languages, in Austria, in parts of Germany (where the other German name Meerrettich is not used), in North-East Italy, and in Yiddish (כריין transliterated as khreyn). It is common in Ukraine (under the name of , khrin), in Belarus (under the name of , chren), in Poland (under the name of ), in the Czech Republic (), in Slovakia (), in Russia (, khren), in Hungary (), in Romania (), in Lithuania (), and in Bulgaria (under the name of ). Cultivation Horseradish is perennial in hardiness zones 2–9 and can be grown as an annual in other zones, although not as successfully as in zones with both a long growing season and winter temperatures cold enough to ensure plant dormancy. After the first frost in autumn kills the leaves, the root is dug and divided. The main root is harvested and one or more large offshoots of the main root are replanted to produce next year's crop. Horseradish left undisturbed in the garden spreads via underground shoots and can become invasive. Older roots left in the ground become woody, after which they are no longer culinarily useful, although older plants can be dug and re-divided to start new plants. The early season leaves can be distinctively different, asymmetric spiky, before the mature typical flat broad leaves start to be developed. Pests and diseases Widely introduced by accident, "cabbageworms", the larvae of Pieris rapae, the small white butterfly, are a common caterpillar pest in horseradish. The adults are white butterflies with black spots on the forewings that are commonly seen flying around plants during the day. The caterpillars are velvety green with faint yellow stripes running lengthwise down the back and sides. Fully grown caterpillars are about in length. They move sluggishly when prodded. They overwinter in green pupal cases. Adults start appearing in gardens after the last frost and are a problem through the remainder of the growing season. There are three to five overlapping generations a year. Mature caterpillars chew large, ragged holes in the leaves leaving the