Horseradish

Plant Overview

Horseradish (Armoracia rusticana) is listed in the Brassicaceae family and categorized as a herb with a perennial life cycle. This profile summarizes growing information for hardiness, light, soil, water, seed starting, maturity, and other available cultivation details. Difficulty is listed as Easy.

Plant ID

PLT-0049

Family

Brassicaceae

Plant type

Herb

Life cycle

Perennial

Alternate names

Red cole

Growth habit

Hardy herbaceous perennial grown for its thick, pungent taproot; root fragments left in the soil can produce new plants

Mature height

About 2-5 feet, depending on variety and growing conditions

Mature spread

Established plants can spread about 2-4 feet across; unharvested roots can form expanding colonies

Difficulty

Easy

Growing Conditions

Horseradish is listed for full sun to partial shade conditions. Water needs are listed as water consistently for good root quality while avoiding waterlogging; drought stress can make roots woody. The database soil reference is Deep, fertile, well-drained soil enriched with organic matter. The listed soil pH range is 6.0-7.5, and the listed hardiness range is 3-9.

Hardiness zones

3-9

Sunlight

Full sun to partial shade

Soil

Deep, fertile, well-drained soil enriched with organic matter

Soil pH

6.0-7.5

Water needs

Water consistently for good root quality while avoiding waterlogging; drought stress can make roots woody

Plant spacing

Plant root cuttings about 12 inches apart; choose a dedicated area where spreading roots can be managed

Seed & Germination

For propagation, the database note is not applicable to the usual method of growing from root or crown cuttings. Planting-depth guidance: For root cuttings rather than seed: plant root pieces about 2-3 inches deep with the end nearest the original crown positioned higher. The listed time to maturity is Allow a full growing season, about 150 days under suitable conditions, for a first-year root harvest. Use these values as general reference points and adjust for local climate, seed source, and growing conditions.

Germination

Not applicable to the usual method of growing from root or crown cuttings

Germination temperature

Not applicable to root or crown cuttings; seed germination is not the standard establishment method

Seed depth

For root cuttings rather than seed: plant root pieces about 2-3 inches deep with the end nearest the original crown positioned higher

Sowing method

Plant root cuttings or crown divisions outdoors in early spring

Start indoors

Usually unnecessary; start the crop outdoors from root or crown pieces

Transplanting

Plant crown divisions in early spring after allowing cut surfaces to heal for several days. Position divisions at about a 45-degree angle with the crown 1-2 inches below the soil surface

Harvest & Propagation

Days to maturity

Allow a full growing season, about 150 days under suitable conditions, for a first-year root harvest

Harvest

Dig roots in autumn after several frosts for improved flavor. Remove tops and side roots, retaining healthy side roots for replanting. Collect unwanted root fragments carefully because pieces left in the soil can regrow and spread

Propagation

Usually propagated from root cuttings or divided crowns

Seed saving

Usually maintained by saving healthy side roots for replanting rather than collecting seed. Retain root cuttings at harvest and keep them cool and moist, without waterlogging, until spring planting

Pollination

Flowers are pollinated by bees, flies, and beetles; pollination is not required for harvesting roots or propagating root cuttings

Garden Information

Common pests

Cabbageworm larvae, mustard leaf beetles, and flea beetles may feed on leaves

Common diseases

Root rot can occur in overly wet soil; white rust and mosaic diseases can also affect susceptible varieties

Uses

Pungent roots grated for sauces, relishes, and condiments