Horseradish is a fast-growing and easy-to-grow perennial and is a member of the Brassicaceae family. Horseradish shares this family tree with broccoli, cabbage, and the mustard plant and is a wonderful accompaniment to pot roast and prime rib.
The root (which is what the plant is mainly grown for) is odorless. It takes an action, such as grating, to cause a reaction, which then causes the release of the oil that can cause irritation of the eyes and sinuses.
Horseradish is best grown where it can be given a spot of its own. Because of its invasive tendencies, it is a good candidate for either raised beds or container growing. Burying a bucket or other type of container in the garden and planting your horseradish in that will also keep it where it belongs. It is also advisable not to plant it in an area where it can be disturbed by tilling or any other activity that would cause the roots to be broken up and distributed throughout the area.
Although horseradish will grow well in partial shade, it will achieve its best growth in full sun. A pH level between 5.5 and 7 is recommended. Horseradish can be planted in the early spring, as soon as the ground can be worked, and can also be planted in the early fall.
If planting horseradish by a root cutting (rather than a plant), dig a hole about as deep as the shovel. Stand the root up (hold it in place, if necessary) and fill the hole in around it, leaving the crown of the root partially exposed. Water well and keep the area surrounding it free of weeds. Continue to keep the new plant lightly watered throughout the summer months.
If you acquire an entire horseradish plant, dig the hole twice as deep as the size of the roots. Fill the dirt in around the roots, making sure that, when you are finished, the base of the leaves are at the top of the soil line. Water well. If the weather is sunny, it might be a good idea to shade the new plant for a few days.
Most commonly, horseradish is harvested in the fall, usually after the first frost, and when the plant is at least 12 to 18 months old. It can, however, also be harvested in the early spring, at which time you might also want to divide your plant or plants (they can also be divided in the fall). To harvest, dig around the base of the plant, exposing the roots. Then, simply break off the amount of root you wish to use, process, or replant for new plants, choosing the best roots that are at least one inch in diameter. Replace the disturbed dirt around the plant.
To process the horseradish roots you have selected, scrub them, removing all dirt. Use a potato peeler to remove the first layer of the outer skin or coating, removing any defective parts. If grating by hand, it is easiest to keep the roots in larger pieces but if you are using a blender or food processor (one of those inexpensive food choppers that are on the market would be ideal), cut the root into small pieces. It might be a good idea to wear rubber gloves, as well as having a window open, when working with your roots.
Once your horseradish is ground to the desired texture, you can add your 5% distilled white vinegar. The strength of your prepared horseradish will depend on at what point you add the vinegar. The longer you wait before adding the vinegar, the stronger – and hotter! – your horseradish will be. For a milder product, add the vinegar immediately after chopping.
Your prepared horseradish will store well in a container with a tight lid in the refrigerator (for up to six weeks) or in the freezer (for six months or longer).