Horseradish (\(Armoracia rusticana\)) is a cold-hardy perennial vegetable valued for its pungent, fleshy root, which belongs to the mustard family (\(Brassicaceae\)). The root is grated to produce the well-known fiery condiment. Unlike many vegetables started from seed, horseradish is almost always propagated using small root cuttings, commonly referred to as “sets” or “thongs.” These vegetative cuttings ensure the new plant carries the exact characteristics of the parent plant, making it simple to grow successfully in a home garden.
Finding Reputable Sources for Planting Material
Locating quality horseradish sets requires looking beyond standard grocery store produce, as these roots are often treated to prevent sprouting. The most reliable source for disease-free and varietally specific planting material is specialized online nurseries and mail-order suppliers. These vendors offer named varieties, such as ‘Maliner Kren’ or ‘Big Top,’ selected for superior root quality. Check customer reviews regarding a nursery’s history of shipping healthy, viable roots before placing an order.
Local garden centers and farm supply stores may carry sets, but availability is seasonal, concentrated in early spring. If shopping locally, inquire about the origin of the root pieces to ensure they have been stored correctly. Another option is acquiring cuttings from established local growers or farmers’ markets, which can provide stock adapted to the regional climate. Inspect this material carefully, as there is a risk of latent pests or disease.
Selecting and Handling Quality Horseradish Sets
When purchasing, the quality of the set directly influences the growth and yield of the mature plant. A healthy set should be firm to the touch and show no signs of mold, discoloration, or softness. Ideally, the root piece should be roughly the diameter of a pencil or slightly thicker and be approximately six to ten inches long. Some professional sets are intentionally cut with a square end on the top and a slanted end on the bottom to indicate the correct planting orientation.
If you cannot plant the sets immediately, proper temporary storage is necessary to maintain viability. Horseradish roots are best stored in a cool, slightly humid environment to prevent them from drying out or rotting. Wrapping the roots in a slightly dampened paper towel and placing them in a perforated plastic bag inside a refrigerator’s crisper drawer is an effective short-term solution. Alternatively, the roots can be buried in moist sand or sawdust in a cold, dark location until the soil is workable for planting.
Planting and Managing Growth
Horseradish thrives in full sun, though it can tolerate partial shade. The plant requires deep, loose, fertile soil, ideally a loamy consistency, to allow the thick taproot to grow straight and unbranched. Before planting, the area should be loosened to a depth of at least 12 inches and amended with well-decayed organic matter.
Planting the set is generally done in early spring as soon as the soil is workable, or sometimes in late fall. The set should be planted at a 45-degree angle, with the top end positioned two to three inches below the soil surface. Ensuring the correct end faces up is important, as the crown end is where the new foliage will sprout.
The primary consideration for long-term management is containing the plant’s aggressive growth, as it can quickly become invasive. Horseradish spreads vigorously through lateral root pieces that can sprout new plants if left unchecked. Consistent watering is only needed during periods of dry weather, as the plant is hardy once established.
Containing Aggressive Spread
A recommended strategy is to plant the sets within large, deep containers, such as five-gallon buckets with the bottoms removed, or in raised beds that are at least 18 inches deep. Physical root barriers, like metal or heavy plastic sheeting, can also be installed. These barriers should be buried 18 to 24 inches deep around the planting area to prevent roots from spreading into other parts of the garden.