Horseradish is a perennial vegetable or herb that is primarily grown for its pungent roots. This is the same horseradish that most people buy in a jar and use to spice up a variety of dishes, from roast beef to cocktail sauce, and to complete a Passover Seder plate. Horseradish leaves can also be eaten when they are young and tender, but they should not be eaten by animals because they are mildly toxic to them.

Horseradish (Armoracia rusticana) is a clump-forming perennial plant in the Brassicaceae family. It is grown from root divisions and can be extremely aggressive. If you worry about horseradish spreading and taking over your garden, you can plant it within barriers—or you can grow it in a container, where you have the option of growing it as an annual plant with a single large root.

Grow new horseradish plants with pieces of root that are about the diameter of a finger and 12 to 18 inches long. It will quickly spread, so you won't need more than one or two plants to feed the whole family. Dig holes about 6 to 8 inches deep and 12 inches apart. Plant one root per hole at a 45-degree angle with the crown, or large end, toward the top at the soil line, and the small end at the base of the hole. Backfill the hole to cover the crown of the root with 2 to 4 inches of soil, then water the plant well.