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When to Plant Horseradish in Jefferson County, FL

Jefferson County, Florida Zone 9a May

What to do in May

If you only do a handful of things in the garden this May, make it these. They're sequenced around your zone's frost timing.

Avg. last frost March 9
Avg. first frost November 21
Soil temp (4") 73°F
Watering Low
Pest pressure High
Daylight 13.5 hrs

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Horseradish is a vigorous perennial grown for its pungent, spicy roots used as a condiment. Once established, it can be difficult to eradicate, so choose its location carefully.

Jefferson County, Florida is in USDA Zone 9a. The average last spring frost is March 9 and the first fall frost is November 21, giving you a growing season of approximately 257 days.

At an elevation of 105 feet, Jefferson County receives approximately 56 inches of rainfall annually with predominantly sand soil. Summer highs average 95°F, so Horseradish may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Horseradish will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Horseradish root diseases.

Jefferson County, FL (Zone 9a) Long season
257 days
Last Spring Frost March 9
257 growing days
First Fall Frost November 21

Jefferson County Soil Profile

Soil Type

Sand

Soil pH

5.2-5.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (42 days to spare)
Transplant: Mar 18 🍅 Harvest: Jul 22 – Sep 30
Recommended (50%) ✓ Fits season (47 days to spare)
Transplant: Mar 23 🍅 Harvest: Jul 27 – Oct 5
Safe Start (90%) ✓ Fits season (50 days to spare)
Transplant: Apr 10 🍅 Harvest: Aug 14 – Oct 23

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Soil Compatibility in Jefferson County

How your county's soil matches Horseradish's growing requirements.

Soil pH

Your soil pH (5.2–5.9) is more acidic than Horseradish prefers (6.0–7.5). Add garden lime to raise pH.

Soil Texture

Sandy soil in Jefferson County warms quickly in spring but drains fast. Horseradish will need more frequent watering and regular compost additions to retain nutrients.

Drainage

Drainage is adequate for Horseradish.

Organic Matter

Organic matter is low (1.3%). Add 2-3 inches of compost before planting Horseradish.

How to Plant Horseradish

1"
Planting Depth
30"
Between Plants
42"
Between Rows

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.9″/week
You supply
0.4″/week
Watering frequency 1-2 times/week
Season total 880 gal / 100 sq ft

Monthly Watering Guide for Horseradish

Horseradish needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Horseradish Needs Rainfall You Supplement Action
Jan 3" 0" ❄️ Dormant
Feb 2.9" 0" ❄️ Dormant
Mar 4.3" 3.2" 1.1" 💧 Light watering
Apr 4.3" 2.4" 1.9" 💧 Light watering
May 4.3" 3.8" 0.5" 💧 Light watering
Jun 4.3" 7.8" 0" ✅ Rainfall sufficient
Jul 4.3" 8.9" 0" ✅ Rainfall sufficient
Aug 4.3" 7.4" 0" ✅ Rainfall sufficient
Sep 4.3" 6.4" 0" ✅ Rainfall sufficient
Oct 4.3" 5" 0" ✅ Rainfall sufficient
Nov 4.3" 2.5" 1.8" 💧 Light watering
Dec 2.7" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Nov in Jefferson County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Horseradish Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Horseradish needs ~3,188 GDD — county provides 5,461 GDD Excellent fit

Horseradish Planting Timeline — Jefferson County, FL

Horseradish Planting Calendar

Activity When Date Range
Transplant Outdoors March 23 Mar 23 – Apr 6
Harvest July 27 Jul 27 – Oct 5

Plant 1" deep · 30" apart · Rows 42" apart

Month-by-Month Timeline

MonthActivities
January
February
March Transplant Outdoors
April Transplant Outdoors
May
June
July Harvest
August Harvest
September Harvest
October Harvest
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · 1-2 times/week

📅 Days to Maturity

120–180 days

🧪 Soil pH

Needs 6–7.5 · Your soil: too_acidic

🗺️ USDA Zone

Zone 9a

📆 Growing Season

257 days in Jefferson County

Growing Tips for Horseradish in Jefferson County

Direct sow Horseradish outdoors after March 09 in Jefferson County when soil has warmed and frost danger has passed.

Sandy soil in Jefferson County dries quickly — mulch Horseradish with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.

Common pests for Horseradish in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.

General growing tips

Plant root cuttings at a 45-degree angle in early spring. Harvest roots in late fall for strongest flavor. Contain the plant with barriers or grow in large containers.

Companion Planting

Good Companions

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Horseradish in Jefferson County, FL?

Jefferson County is in Zone 9a with an average last frost of March 9. Plan your Horseradish planting based on this frost date — see the calendar above for exact timing.

What planting zone is Jefferson County, FL?

Jefferson County, Florida is in USDA Hardiness Zone 9a. The average last spring frost is March 9 and first fall frost is November 21.

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Your Jefferson County Garden Planner — Free

A 24-page printable planner built for Jefferson County (Zone 9a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Jefferson County, FL. Local conditions may vary. Last updated: May 2026.

Sources & credits

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