Horseradish is one of the most cold-tolerant root crops I grow, and the timing of planting—whether you garden in a cold-winter region or a mild climate—can make a big difference in root quality, heat, and size. After decades growing horseradish in raised beds and open ground, I’ve learned that planting at the right time ensures steady growth and an easy harvest.

This guide walks you through the best planting windows, how timing changes across climate zones, and a clear month-by-month planting calendar.

🗓️ General Planting Rule for Horseradish

Horseradish is almost always planted from root cuttings (sets) rather than seeds. The key is to plant when the soil is workable and cool but not frozen.

Best Overall Window

Plant horseradish in early spring as soon as the soil can be worked.
This usually means:

Soil temperature above 45°F (7°C)
Ground no longer frozen
Beds not saturated with winter moisture

Why Early Spring Works Best

Encourages strong top growth before summer heat
Promotes long, straight root formation
Reduces stress and improves flavor
Matches horseradish’s natural cool-season growth pattern

In mild climates—including my Sonoma Valley garden—you can also plant in fall for a winter-to-spring crop.

🌍 Planting Time by Climate Zone

Horseradish adapts well from Zone 3 to Zone 10, but planting windows shift with temperature and winter conditions.

Cold Climates (Zones 3–6)

Best Planting Time: Early to mid-spring
Typical Window: March–May

Notes:

The ground must be workable, not frozen
Earlier planting leads to larger fall roots
Avoid fall planting—roots may freeze and rot

Mild Climates (Zones 7–8)

Best Planting Time: Early spring or early fall
Typical Windows:

February–April
September–October

Notes:

Spring planting is most reliable
Fall planting works well if winters are not excessively wet
Mulch lightly to protect fall plantings

Warm Climates (Zones 9–10)

Best Planting Time: Late fall through winter
Typical Window:

October–February

Notes:

Horseradish struggles in hot summers
Planting in fall allows strong cool-season growth
Afternoon shade improves summer survival
Annual growing is often the best method here

📅 Month-by-Month Planting Calendar

Below is a simplified, climate-aligned calendar based on decades of horseradish growing experience.

January

Zones 9–10: Plant now
Zones 7–8: Prepare beds, avoid planting

February

Zones 7–10: Plant horseradish sets
Zones 5–6: Prepare soil, warm beds under plastic

March

Zones 5–7: Prime planting month
Zones 3–4: Plant as soon as soil thaws
Zones 8–10: Final month for planting

April

Zones 3–6: Excellent planting month
Zone 7: Last call for spring planting

May

Zones 3–5: Final month for planting
Zones 6–7: Only plant if soil is still cool

June–August

Do not plant horseradish in summer—heat suppresses root growth.

September

Zones 7–8: Fall planting window opens
Zones 9–10: Planting is ideal now

October

Zones 7–10: Prime fall planting month

November

Zones 9–10: Continue planting
Zones 7–8: Plant early in month only

December

Zones 9–10: Continue planting
All other zones: Dormant period

🧑‍🌾 My Recommendation

For most gardeners, plant horseradish as soon as your soil is workable in spring.
This timing gives the plant a full cool season to establish deep, flavorful roots.

If you garden where summers are hot or winters are mild, consider fall planting for a strong cool-season growth cycle.