Blog

When to Plant Radish in Jefferson County, AR

Radishes are one of the fastest-growing vegetables, with some varieties ready in under a month. They come in round, elongated, and large winter types.

Jefferson County, Arkansas is in USDA Zone 7b. The average last spring frost is March 19 and the first fall frost is November 9, giving you a growing season of approximately 235 days.

At an elevation of 454 feet, Jefferson County receives approximately 51.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89ยฐF, providing good warmth for Radish during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Radish root diseases.

Jefferson County, AR (Zone 7b) Long season
235 days
Last Spring Frost March 19
235 growing days
First Fall Frost November 9

Jefferson County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-7.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (187 days to spare)
Transplant: Mar 10 🍅 Harvest: Apr 7 – Apr 28
Recommended (50%) ✓ Fits season (186 days to spare)
Transplant: Mar 19 🍅 Harvest: Apr 16 – May 7
Safe Start (90%) ✓ Fits season (184 days to spare)
Transplant: Apr 8 🍅 Harvest: May 6 – May 27

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 Radish's growing requirements.

Soil pH

Your soil pH (5.3โ€“7.1) overlaps with Radish's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

The silt loam soil in Jefferson County is excellent for Radish โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.5%). Annual compost additions will help Radish.

How to Plant Radish

0.5"
Planting Depth
2"
Between Plants
6"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Radish

13
successive plantings in your 235-day season

Sow every 2.4 weeks. Last sowing by Oct 05 to harvest before frost.

For a dedicated fall crop, sow by Aug 31.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
0.9″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Radish

Radish needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.

Month Radish Needs Rainfall You Supplement Action
Jan โ€” 4" 0" โ„๏ธ Dormant
Feb โ€” 3.9" 0" โ„๏ธ Dormant
Mar 2.2" 5.4" 0" โœ… Rainfall sufficient
Apr 2.2" 3.7" 0" โœ… Rainfall sufficient
May 2.2" 4.1" 0" โœ… Rainfall sufficient
Jun 2.2" 4.3" 0" โœ… Rainfall sufficient
Jul 2.2" 5.5" 0" โœ… Rainfall sufficient
Aug 2.2" 5.1" 0" โœ… Rainfall sufficient
Sep 2.2" 3.4" 0" โœ… Rainfall sufficient
Oct 2.2" 3.7" 0" โœ… Rainfall sufficient
Nov 2.2" 4.4" 0" โœ… Rainfall sufficient
Dec โ€” 3.9" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Nov in Jefferson County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Radish 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" โ€” every day above 50ยฐF 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.

Radish needs ~477 GDD — county provides 3,936 GDD Excellent fit

Radish Planting Timeline โ€” Jefferson County, AR

Radish Planting Calendar

Activity When Date Range
Direct Sow March 5 Mar 5 โ€“ Mar 26
Harvest April 2 Apr 2 โ€“ Apr 23
Fall Sowing August 31 Aug 31 โ€“ Sep 14

Plant 0.5" deep ยท 2" apart ยท Rows 6" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Direct Sow
April Harvest
May โ€”
June โ€”
July โ€”
August Fall Sowing
September Fall Sowing
October โ€”
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.5"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

22โ€“35 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 7b

๐Ÿ“† Growing Season

235 days in Jefferson County

Growing Tips for Radish in Jefferson County

Direct sow Radish outdoors after March 19 in Jefferson County when soil has warmed and frost danger has passed.

Your generous 235.0-day season in Jefferson County allows multiple plantings of Radish. Sow every 11.0 days for continuous harvest.

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

General growing tips

Direct sow every 1-2 weeks for continuous harvest. Do not transplant. Harvest spring radishes promptly to prevent them from becoming pithy and hot.

Companion Planting

Good Companions

Avoid Planting Near

  • Hyssop

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Radish in Jefferson County, AR?

Jefferson County is in Zone 7b with an average last frost of March 19. Plan your Radish planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Jefferson County, AR?

Jefferson County, Arkansas is in USDA Hardiness Zone 7b. The average last spring frost is March 19 and first fall frost is November 9.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Jefferson County gardeners in Zone 7b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

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