Authored by: Carol Shirk
In my mother’s Slovak kitchen, no meal would be complete without some horseradish in one form or another. Grated horseradish in beets, a dab of ground horseradish beside our meat for dipping, meat in a creamed horseradish sauce, or some in our meatloaf, potato salad, and scrambled eggs were just some of the places she would hide it. If you did not grow up with this fiery herb, it may take a bit to appreciate it, but it will be well worth the try.
Horseradish (Armoracia rusticana) is a hardy perennial that grows well in our Wisconsin climate. It is native to Russia and Eastern Europe (which explains my mother’s frequent use; she was a first generation American), and has been used for thousands of years as a condiment. The colonists brought it to North America and it is now grown in most parts of the world. Most of the U.S. commercial cultivation is in California, New Jersey, Virginia, Wisconsin, and Illinois.
If you are a horseradish fan, or if you just want to try something different, it is an easy-to-grow root crop. You will not need much experience or much effort to grow horseradish. It likes full sun, but will tolerate some shade. Well drained, loose, rich loamy soil is ideal. Heavy clay will result in malformed roots and water-logged soils will cause root rot.
Before planting, loosen the soil to a depth of 8–12 inches. Plant the root cuttings in the spring as soon as the soil can be worked, spacing them about a foot apart and placing them either vertically or at a 45-degree angle. Make sure the top of the root is at or just below soil level. Add a bit of compost at planting time. Because horseradish is a vigorous grower, no further fertilization will be necessary.
Weed control is important early in the season. Be sure to cultivate in the direction you planted the sets, following along the angle you placed them so that you do not sever any roots. Organic mulch around the plants will help keep the weeds at bay as well as keep the soil moist.
To get nice, strong, straight roots at harvest time, strip the roots when the plants are about a foot tall. To do so, gently remove the soil around the top of the root and carefully trim away all small roots, leaving the bottom roots intact. Replace the soil. Remove all but the best 2 or 3 crown of leaves. Repeat this process in 4-6 weeks.
Horseradish can either be harvested in the fall once frost has killed the foliage or in the spring when growth resumes. Using a garden fork, carefully lift the roots, making sure to get every piece. Any small piece of root with resume growth and you will have a perennial horseradish bed whether you want it or not. Harvest the main root for use and save the lateral roots for replanting. Spring planted roots are best left to harvest until the following spring; year old roots have the best flavor.
The primary problem with horseradish is controlling the growth. One way to prevent a perennial bed is to bury a large tub with the bottom cut out and plant in it to prevent escape. Do not till the bed. Cutting up any small roots will result in many more plants. Horseradish can spread and out-compete surrounding plants rather rapidly.
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