Grow horseradish from crowns or root cuttings planted four to six weeks before the average date of the last frost for your area. Horseradish is a hardy perennial best grown as an annual. Keep horseradish from spreading in the garden by growing it in a container.
Description. Horseradish is a hardy perennial grown for its pungent roots which are long and narrow, sometimes to 2 feet (.6m) long. Grow horseradish as an annual, in the second year the roots can become tough and fibrous. Horseradish is best grown in containers; it spreads readily and can easily grow out of control. Horseradish will be ready for harvest 140 to 160 days after planting.
Yield. Allow 1 plant per household
Site. Plant horseradish in full sun; it will tolerate partial shade. Grow horseradish in rich well-drained soil. Prepare the soil to a depth of 10 to 12 inches (25-30cm) and remove stones and lumps that might cause the roots to split. Add sand and compost to the planting bed to keep the soil loose. Horseradish prefers a soil pH of 5.5 to 6.8.
Planting time. Horseradish is a cold-hardy plant. Set out crowns or root cuttings 4 to 6 weeks before the average last frost date in your region. Horseradish grows best in cool, moist regions where the temperature stays between 45°F and 75°F (7-24°C).
Planting and spacing. Set crowns just at soil level. Plant roots in shallow trenches 3 to 4 inches (7-10cm) deep and cover with 2 to 3 inches (5-7cm) of soil. Slice root cuttings at a 30-degree angle or plant with the narrow end down; fill the trench until the wide end of the root is just covered. Space roots 24 to 36 inches (61-91cm) apart. Horseradish planted in the garden should be contained with wooden, metal, or masonry borders set at least 24 inches (61cm) deep around the bed.
Companion plants. Potatoes, yams
Container growing. Choose a container that will allow horseradish roots to grow 24 to 30 inches (61-76cm) deep.
Water and feeding. Keep the soil evenly moist to prevent roots from drying and turning woody. Fertilize horseradish by adding organic compost to the planting bed every month.
Care. To grow a large taproot root use a spade to slice down around the plant 3 to 4 inches (7-10cm) from the base pruning away side roots. Avoid leaving pieces of the root in the ground after harvest, they will produce a new plant the next year.
Pests. Horseradish has no serious pest problems.
Diseases. Horseradish has no serious disease problems
Harvesting and Storing Horseradish
Harvest. Cut sections of root for use as needed after leaves are about 12 inches (30cm) long (roots will then be 3 to 4 inches/7-10cm in diameter). Horseradish makes its best growth in late summer and fall, so delay harvesting until mid-autumn or later. Harvest all root before the ground freezes otherwise new plants will spring up the following year.
Storing and preserving. Grated horseradish can be kept in a glass jar in the refrigerator for one to two weeks. Whole roots can be packed in damp sawdust and kept for up to 10 months. To freeze horseradish, grate the roots and mix with vinegar and water.
Varieties. Horseradish is non-varietal.
Common name. Horseradish
Botanical name. Armoracia rusticana
Origin. Eastern Europe