Vegetable · Perennial root vegetable
Horseradish
Armoracia rusticanaA tough, cold-hardy perennial grown for its pungent, fiery root rather than its coarse leaves. Once established from a root cutting it spreads readily, so most gardeners confine it to a bottomless bucket or a bin. The one rule: dig out every scrap of root when you want to be rid of it — any fragment left behind will resprout.
Sow depth
N/A — plant root cuttings
Spacing
12 in · rows 2.5 ft
Sun
Full sun
Germination
N/A — grown from root cuttings
Time to harvest
140–160 days
Difficulty
Easy
When to sow horseradish
- Sow from about 6 weeks before your last expected frost until about 2 weeks before your last expected frost.
Plant root cuttings, not seed — set "thongs" 2–3 in deep at a 45° angle, thin end down.Choose deeply dug, stone-free soil so roots grow straight instead of forking.Confine roots in a bottomless bucket or raised bed — any leftover piece will resprout.
Water through dry spells — consistent moisture grows straighter, larger roots.Weed around young shoots; established plants soon shade out competition.Rub off side roots that form along the crown so growth stays in the main root.
Wait until after fall frost — cold weather concentrates the root’s heat and flavor.Dig the whole root with a fork just before the ground freezes solid.Store roots in damp sand, or leave them in the ground and dig as needed through winter.
Companion plants
Planted near potatoes, horseradish is thought to help repel the Colorado potato beetle and other root pests.
Watch out for
Horseradish flea beetle — Rasps small holes in leaves through summer. Cover young growth with fine mesh, or accept the damage — roots are unaffected.Root rot — Sets in on waterlogged ground. Plant in raised, well-drained soil and rotate the bed every few years.