Blog

When to Plant Horseradish in Carlisle County, KY

Carlisle County, Kentucky Zone 7a May

Your May gardening checklist

May rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Carlisle County, Kentucky.

Avg. last frost March 28
Avg. first frost October 31
Soil temp (4") 54°F
Watering Moderate
Pest pressure Low
Daylight 14 hrs

Instant PDF download. No spam, unsubscribe any time.

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.

Carlisle County, Kentucky is in USDA Zone 7a. The average last spring frost is March 28 and the first fall frost is October 31, giving you a growing season of approximately 217 days.

At an elevation of 4,000 feet, Carlisle County receives approximately 44.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90°F, providing good warmth for Horseradish during the growing season.

Carlisle County, KY (Zone 7a) Long season
217 days
Last Spring Frost March 28
217 growing days
First Fall Frost October 31
Share this guide:

Carlisle County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (10 days to spare)
Transplant: Apr 2 🍅 Harvest: Aug 6 – Oct 15
Recommended (50%) ✓ Fits season (7 days to spare)
Transplant: Apr 11 🍅 Harvest: Aug 15 – Oct 24
Safe Start (90%) ✓ Fits season (1 days to spare)
Transplant: Apr 29 🍅 Harvest: Sep 2 – Nov 11

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 Carlisle County

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

Soil pH

Your soil pH (5.7–6.7) overlaps with Horseradish's range (6.0–7.5), though not a perfect match.

Soil Texture

The silt loam soil in Carlisle County is excellent for Horseradish — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.6%). 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
0.9″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 264 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 4" 0" ❄️ Dormant
Feb 3.9" 0" ❄️ Dormant
Mar 4.3" 4.1" 0.2" 💧 Light watering
Apr 4.3" 3.4" 0.9" 💧 Light watering
May 4.3" 3.7" 0.6" 💧 Light watering
Jun 4.3" 3.6" 0.7" 💧 Light watering
Jul 4.3" 4.8" 0" ✅ Rainfall sufficient
Aug 4.3" 4.3" 0" ✅ Rainfall sufficient
Sep 4.3" 3.2" 1.1" 💧 Light watering
Oct 4.3" 2.6" 1.7" 💧 Light watering
Nov 3.2" 0" ❄️ Dormant
Dec 3.7" 0" ❄️ Dormant

Water needs are for active growing months only (Mar–Oct in Carlisle 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 ~2,625 GDD — county provides 3,797 GDD Excellent fit

Horseradish Planting Timeline — Carlisle County, KY

Horseradish Planting Calendar

Activity When Date Range
Transplant Outdoors April 11 Apr 11 – Apr 25
Harvest August 15 Aug 15 – Oct 24

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

Month-by-Month Timeline

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

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 7a

📆 Growing Season

217 days in Carlisle County

Growing Tips for Horseradish in Carlisle County

Direct sow Horseradish outdoors after March 28 in Carlisle County when soil has warmed and frost danger has passed.

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 Carlisle County, KY?

Carlisle County is in Zone 7a with an average last frost of March 28. Plan your Horseradish planting based on this frost date — see the calendar above for exact timing.

What planting zone is Carlisle County, KY?

Carlisle County, Kentucky is in USDA Hardiness Zone 7a. The average last spring frost is March 28 and first fall frost is October 31.

🌱

Your Carlisle County Garden Planner — Free

A 24-page printable planner built for Carlisle County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Carlisle County, KY. 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.