The grated horseradish one finds in a jar in the refrigerated section of the grocery stores is a rugged, cold hardy (hardy to zone 3) root. It is easy to grow, rarely suffering any disease.
Choosing a site:
Horseradish thrives in full sun but tolerates light shade. It will adapt to any soil condition except waterlogged areas. Consider it a permanent residence. It will provide many years of harvest, but does not like to be moved.
Plant roots in the spring. Loosen the soil to 12 inches deep, adding a shovelful of compost. Plant the root at a 45 degree angle with the top 2 inches below the soil line. One root is sufficient for an abundant harvest.
Horseradish needs little or no attention in order to thrive. To keep the plant from looking ratty, however, water it once a week during dry spells and couple a couple of inches of mulch around the plant to help conserve moisture.
You can enjoy your first horseradish harvest one year after planting. Carefully dig away the soil from around the main root, taking care to free up the side roots and remove them at the same time. Harvest after a hard frost kills the foliage. Scrub main root under running water and dry well. If enclosed in a perforated plastic bag, horseradish root will keep in the vegetable bin of your refrigerator for 3 months or longer.
Freshly grated horseradish emits fumes that can make your nose run and irritate your eyes, so prepare it in a well¬ventilated area. First peel a 3 to 4¬inch section of root as you would a carrot. Cut it in half¬inch chunks and drop them in a blender or food processor. Add ¼ cup cold water and a bit of crushed ice and grind to a fine texture. Have some white wine vinegar or rice wine vinegar.
Hot or Not?
Customize the heat of your horseradish sauce by adding the vinegar immediately for mild horseradish, either right after grinding is complete or as you are still grinding. If you like stronger flavor, wait 3 minutes to add the vinegar. Add 2¬3 Tbs. vinegar and ½ tsp. salt for each cup of grated horseradish. In either case, pulse the machine to blend in the final ingredients. If your preparation has too much liquid, simply drain some of it off through a fine strainer until you get the consistency you want. Store in a clean jar in the refrigerator for up to 4 to 6 weeks.