Planting Horseradish
Horseradish is a cool season vegetable in the Brassicaceae family. Getting the timing right is the difference between a strong stand and a disappointing one, so the windows below are given relative to your own last spring frost and first fall frost rather than a generic calendar date. Look up your local frost dates and count back or forward from there.
Transplant young plants outdoors 2–4 weeks before your last frost — Horseradish tolerates cool conditions and benefits from an early start.
Spacing and Planting Depth
Give Horseradish room to mature. The figures below come from verified extension and seed-supplier data for typical varieties.
| Spacing in row | 18 inches |
|---|---|
| Row spacing | 30 inches |
| Plants per sq ft | 0.27 |
| Planting depth | 3 inches |
| Sun requirement | Full sun |
Days to Maturity
Horseradish reaches maturity in 140–180 days from sowing.
Horseradish is ready to harvest after about 160 days. Harvest before summer heat or, for fall crops, before a hard freeze, to keep quality high.
Conditions and Care
As a cool-season vegetable, Horseradish does its best growing in the cooler weather of spring and fall and tends to bolt or turn bitter in summer heat. It is frost hardy and can shrug off light freezes, so it can stay in the ground later into the season than tender crops.
Horseradish needs full sun — give it at least six hours of direct light a day for the best growth and flavor. Sow seed about 3 inches deep, then keep the soil evenly moist until seedlings establish.
Horseradish belongs to the Brassicaceae family; rotating where you grow members of this family each year helps limit the build-up of soil-borne pests and disease. Horseradish is generally grown as a single planting each season rather than succession sown.
Companion Plants
Pairing Horseradish with the right neighbors can improve growth and deter pests; a few combinations are best avoided.
Grows well with: Potato
Growing Notes
Perennial; grown from root cuttings. Spreads aggressively.