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When to Plant Horseradish in Galveston County, TX

Galveston County, Texas Zone 9b May

Your May gardening checklist

Each item below is timed to Galveston County, Texas's frost dates and soil temperatures. Skip nothing, stress about nothing.

Avg. last frost February 5
Avg. first frost December 7
Soil temp (4") 76°F
Watering Low
Pest pressure High
Daylight 13.5 hrs
A few tasks this May that'll pay off in June
  • First harvests: horseradish

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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.

Galveston County, Texas is in USDA Zone 9b. The average last spring frost is February 5 and the first fall frost is December 7, giving you a growing season of approximately 305 days.

At an elevation of 9 feet, Galveston County receives approximately 72.5 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 100°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.

Galveston County, TX (Zone 9b) Year-round
305 days
Last Spring Frost February 5
305 growing days
First Fall Frost December 7
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Galveston County Soil Profile

Soil Type

Sandy Loam

Soil pH

5.7-6.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (107 days to spare)
Transplant: Feb 1 🍅 Harvest: Jun 7 – Aug 16
Recommended (50%) ✓ Fits season (95 days to spare)
Transplant: Feb 19 🍅 Harvest: Jun 25 – Sep 3
Safe Start (90%) ✓ Fits season (82 days to spare)
Transplant: Mar 20 🍅 Harvest: Jul 24 – Oct 2

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 Galveston County

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

Soil pH

Your soil pH (5.7–6.5) overlaps with Horseradish's range (6.0–7.5), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.1%). Annual compost additions will help Horseradish.

How to Plant Horseradish

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

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
Watering frequency Only during dry spells
Season total 13 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 2.1" 0" ❄️ Dormant
Feb 4.3" 2.2" 2.1" 💧 Light watering
Mar 4.3" 5.4" 0" ✅ Rainfall sufficient
Apr 4.3" 8.2" 0" ✅ Rainfall sufficient
May 4.3" 10.4" 0" ✅ Rainfall sufficient
Jun 4.3" 10.9" 0" ✅ Rainfall sufficient
Jul 4.3" 8.7" 0" ✅ Rainfall sufficient
Aug 4.3" 8.6" 0" ✅ Rainfall sufficient
Sep 4.3" 6.2" 0" ✅ Rainfall sufficient
Oct 4.3" 5.2" 0" ✅ Rainfall sufficient
Nov 4.3" 2.6" 1.7" 💧 Light watering
Dec 4.3" 1.9" 2.4" 🚿 Regular watering

Water needs are for active growing months only (Feb–Dec in Galveston 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 ~3,750 GDD — county provides 7,650 GDD Excellent fit

Horseradish Planting Timeline — Galveston County, TX

Horseradish Planting Calendar

Activity When Date Range
Transplant Outdoors February 19 Feb 19 – Mar 5
Harvest June 25 Jun 25 – Sep 3

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

Month-by-Month Timeline

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

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

120–180 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 9b

📆 Growing Season

305 days in Galveston County

Growing Tips for Horseradish in Galveston County

Direct sow Horseradish outdoors after February 05 in Galveston County when soil has warmed and frost danger has passed.

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

With summer highs reaching 100°F in Galveston County, provide afternoon shade for Horseradish and water deeply in the morning.

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 Galveston County, TX?

Galveston County is in Zone 9b with an average last frost of February 5. Plan your Horseradish planting based on this frost date — see the calendar above for exact timing.

What planting zone is Galveston County, TX?

Galveston County, Texas is in USDA Hardiness Zone 9b. The average last spring frost is February 5 and first fall frost is December 7.

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Your Galveston County Garden Planner — Free

A 24-page printable planner built for Galveston County (Zone 9b). 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 Galveston County, TX. Local conditions may vary. Last updated: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.