Growing horseradish in home gardens

Tie cleaned root cuttings in small bundles and place them in moist sand. Overwinter horseradish in a root cellar or basement that stays between 32 and 40 degrees Fahrenheit during the winter. Do not expose the roots to light otherwise they become green.

Armoracia rusticana

Native to Eastern Europe and Western Asia, Horseradish was brought to the US by colonists and is now grown worldwide.

This plant is a herbaceous perennial herb in the cabbage family with a deep taproot that is often grown as annual vegetable. As a vegetable, it is grown for its fleshy roots that are harvested and grated to make relish, sauces, and seasonings. They have a hot, bitter taste that comes from mustard oils that are released when the plant cells are cut or damaged. The pungency will begin to degrade and take on a bitter taste if not mixed with vinegar, which will stop the degradation. The oils (glucosinolates) can also cause your eyes to water.

Its vigorous growth habit will allow it to smother out other vegetation, including weeds. This is particularly true if the plant is not harvested each fall. Leaving roots in the ground in lieu of harvesting will promote growth in the off months.

Although clay soils tolerant, planting in lighter soils will make harvesting the roots easier.

Propagation can be done annually by removing the roots and storing them for planting the following year.

Insects, Diseases and Other Plant Problems: It can be difficult to eliminate due to its deep taproot. The smallest piece left in the soil can take root and grow into another plant. The leaves are occasionally eaten by cabbage worm larvae and flea beetles.

• ‘Variegata’
  Variable markings appear on established plants

• ‘Variegata’
  Variable markings appear on established plants

• Attributes: Genus: Armoracia Species: rusticana Family: Brassicaceae Uses (Ethnobotany): Condiment Life Cycle: Perennial Recommended Propagation Strategy: Division Root Cutting Country Or Region Of Origin: S. Ukraine to European Russia Distribution: Worldwide distribution Wildlife Value: It is pollinated by bees, flies and beetles. Play Value: Attracts Pollinators Edibility: Edible parts: roots, used as a condiment, but only in small amounts (do not eat large amounts of the roots as eating large amounts may result in poisonous symptoms); leaves, as expand in the spring, may be boiled in salted water until tender, then eaten with butter or margarine Dimensions: Height: 2 ft. 0 in. – 2 ft. 6 in. Width: 2 ft. 6 in. – 3 ft. 0 in.

• Whole Plant Traits: Plant Type: Herb Herbaceous Perennial Perennial Habit/Form: Spreading Growth Rate: Rapid Maintenance: High Texture: Coarse

• Cultural Conditions: Light: Full sun (6 or more hours of direct sunlight a day) Partial Shade (Direct sunlight only part of the day, 2-6 hours) Soil Texture: Clay High Organic Matter Loam (Silt) Sand Soil pH: Acid (<6.0) Alkaline (>8.0) Neutral (6.0-8.0) Soil Drainage: Good Drainage Moist Available Space To Plant: 12 inches-3 feet NC Region: Coastal Mountains Piedmont USDA Plant Hardiness Zone: 4a, 4b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b

• Fruit: Display/Harvest Time: Fall Fruit Type: Capsule Fruit Length: < 1 inch Fruit Width: < 1 inch Fruit Description: Oblong seed pods form after flowering. Each can contain up to 8 seeds. Rarely produces viable seeds in cold winter climates.

• Flowers: Flower Color: White Flower Inflorescence: Panicle Raceme Flower Bloom Time: Spring Flower Petals: 4-5 petals/rays Flower Size: < 1 inch Flower Description: The non-showy flowers are small, white, and 4-parted. They form in panicles or racemes up to 16" long.

• Leaves: Leaf Feel: Glossy Leaf Value To Gardener: Fragrant Leaf Type: Simple Leaf Arrangement: Alternate Leaf Shape: Elliptical Oblong Leaf Margin: Serrate Hairs Present: No Leaf Length: > 6 inches Leaf Width: 3-6 inches Leaf Description: The dark green basil leaves can grow up 2′ long and 6″ wide. The stem leaves grow to 6″ long and 2″ wide. They are alternate, simple, and the margin is toothed. As they ascend the stem, the leaves become smaller.

• Stem: Stem Color: Green Stem Is Aromatic: No Stem Surface: Smooth (glabrous)

• Landscape: Landscape Theme: Edible Garden Attracts: Bees Pollinators Problems: Weedy

Armoracia rusticana

NC State University and N.C. A&T State University work in tandem, along with federal, state and local governments, to form a strategic partnership called N.C. Cooperative Extension, which staffs local offices in all 100 counties and with the Eastern Band of Cherokee Indians.

N.C. Cooperative Extension prohibits discrimination and harassment on the basis of race, color, national origin, age, sex (including pregnancy), disability, religion, sexual orientation, gender identity, and veteran status.

Growing horseradish in home gardens

Horseradish, Armoracia rusticana, is a large-leaved, hardy European perennial herb that has been a culinary favorite for more than 3,000 years.

This fiery herb thrives in temperate climates and in the cool, high altitudes of tropical countries. Horseradish grows best in deep, rich, moist loamy soil, in a sunny location. Roots become malformed and yields are less on hard, shallow, stony soils.

Soil fertility and preparation

• Before planting horseradish, spade, or rototill the soil to a depth of 8 to 10 inches.
• Turn under or mix in generous amounts of well-decayed compost or other organic material.
• Incorporate a complete garden fertilizer (10-10-10) at a rate of one pound per 100 square feet or a large amount of well-decayed manure into the soil.
• Fresh or partly fresh manure used before planting will cause excessive top growth and forked roots.
• Let the worked-up soil settle a few days before planting.

Planting root cuttings

• Plant root cuttings, sometimes called “sets,” in early spring as soon as the soil is workable.
• Space the sets one foot apart, setting them vertically or at a 45-degree angle.
• If angled, make sure that the tops point along the rows in the same direction. This makes cultivating easier.
• Cover the sets with two to three inches of soil.

How to keep your horseradish healthy and productive

Plus sign (+) if content is closed, ‘X’ if content is open.

• Weed control is especially important early in the season when the plants are relatively small.
• It is best to cultivate in the same direction that you planted the sets.
• Mulch around each plant with organic material such as compost or leaves. It will benefit the plants by retaining moisture in the soil, keeping the soil cooler and controlling weeds.

Plus sign (+) if content is closed, ‘X’ if content is open.

Lifting and stripping roots

• To grow high-quality horseradish, lift and strip the roots twice.
• Do it first when the biggest leaves are 8 to 10 inches long and again six weeks later.
• To lift and strip, carefully remove the soil from around the upper ends of the main root. Leave roots at the lower end of the set undisturbed.
• Raise the crown and remove all but the best sprout or crown of leaves.
• Rub off all small roots from the crown and sides of the main root, leaving only those at the bottom. Return the set to its original position and replace the soil.

Plus sign (+) if content is closed, ‘X’ if content is open.

Horseradish grows the most during late summer and early autumn. For this reason, delay fall harvest until late October or early November, or just before the ground freezes.

Harvest by digging a trench 12 to 24 inches deep along one side of the row. Working from the opposite side of the row with a shovel or spading fork, dig the roots. Use the tops as a handle for pulling them laterally from the soil.

Trim the green tops so there is only one inch left. Trim off side and bottom roots. Save roots that are eight inches and longer for next spring’s planting stock. Cut the roots squarely across at the top and slope towards the bottom. This will make it easier to know which end to set upright at planting time.

Tie cleaned root cuttings in small bundles and place them in moist sand. Overwinter horseradish in a root cellar or basement that stays between 32 and 40 degrees Fahrenheit during the winter. Do not expose the roots to light otherwise they become green.

If you cannot have the right storage and temperature conditions, harvest horseradish in spring rather than fall. Dig the roots as soon as new growth starts to appear in spring. Replant lateral roots for next spring’s crop. Roots left in the ground for two growing seasons become stringy and woody.

Plus sign (+) if content is closed, ‘X’ if content is open.

Storage and use

Store horseradish roots for fresh grinding in dark plastic wrapping in the refrigerator. Protect the roots from light to prevent them from turning green.

The most common way to prepare horseradish for table use is to peel or scrape the roots. Grate the root directly into white wine vinegar or distilled vinegar. Avoid using cider vinegar, as it causes discoloration in the grated horseradish within a rather short time. Depending on your preference, you can slightly dilute the vinegar.

Bottle the horseradish and cap the containers as soon as possible after grating. Refrigerate at all times to preserve the pungent flavor. Freshly grated horseradish will keep only for a few weeks. Then prepare a fresh supply.

You can also dry horseradish, ground it into a powder and put it up in bottles in a dry form. Dried horseradish will keep much longer than the freshly grated product, but is not as high quality.

Managing pests, diseases and disorders

Many things can affect horseradish roots and leaves. Changes in physical appearance and plant health can be caused by the environment, plant diseases, insects and wildlife. In order to address what you’re seeing, it is important to make a correct diagnosis.

You can find additional help identifying common pest problems by using the online diagnostic tools or by sending a sample to the UMN Plant Disease Diagnostic Clinic. You can use Ask a Master Gardener to share pictures and get input.

Insects

Flea beetles can cause serious damage to horseradish leaves.

Diseases

Horseradish is susceptible to a variety of root rots.

• Start with disease-free cuttings when starting a new horseradish planting.
• Rotate the horseradish planting site, making sure to not plant in the same place more often than every three to four years.