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When to Plant Radish in White County, IL

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.

White County, Illinois is in USDA Zone 6a. The average last spring frost is April 8 and the first fall frost is October 27, giving you a growing season of approximately 202 days.

At an elevation of 788 feet, White County receives approximately 30.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 85ยฐF, providing good warmth for Radish during the growing season.

White County, IL (Zone 6a) Long season
202 days
Last Spring Frost April 8
202 growing days
First Fall Frost October 27

White County Soil Profile

Soil Type

Silt Loam

Soil pH

5.8-7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (152 days to spare)
Transplant: Apr 2 🍅 Harvest: Apr 30 – May 21
Recommended (50%) ✓ Fits season (153 days to spare)
Transplant: Apr 8 🍅 Harvest: May 6 – May 27
Safe Start (90%) ✓ Fits season (159 days to spare)
Transplant: Apr 20 🍅 Harvest: May 18 – Jun 8

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 White County

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

Soil pH

Your soil pH (5.8โ€“7.0) overlaps with Radish's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is excellent (4.7%) โ€” Radish will thrive.

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

11
successive plantings in your 202-day season

Sow every 2.4 weeks. Last sowing by Sep 22 to harvest before frost.

For a dedicated fall crop, sow by Aug 18.

Plant Water Budget

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

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

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€” 1.1" 0" โ„๏ธ Dormant
Feb โ€” 1.3" 0" โ„๏ธ Dormant
Mar โ€” 2.1" 0" โ„๏ธ Dormant
Apr 2.2" 3.2" 0" โœ… Rainfall sufficient
May 2.2" 3.5" 0" โœ… Rainfall sufficient
Jun 2.2" 3.6" 0" โœ… Rainfall sufficient
Jul 2.2" 3.4" 0" โœ… Rainfall sufficient
Aug 2.2" 3.5" 0" โœ… Rainfall sufficient
Sep 2.2" 2.4" 0" โœ… Rainfall sufficient
Oct 2.2" 2.5" 0" โœ… Rainfall sufficient
Nov โ€” 2.1" 0" โ„๏ธ Dormant
Dec โ€” 1.8" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in White 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 ~392 GDD — county provides 2,777 GDD Excellent fit

Radish Planting Timeline โ€” White County, IL

Radish Planting Calendar

Activity When Date Range
Direct Sow March 25 Mar 25 โ€“ Apr 15
Harvest April 22 Apr 22 โ€“ May 13
Fall Sowing August 18 Aug 18 โ€“ Sep 1

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

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Direct Sow
April Direct Sow Harvest
May Harvest
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 6a

๐Ÿ“† Growing Season

202 days in White County

Growing Tips for Radish in White County

Direct sow Radish outdoors after April 08 in White County when soil has warmed and frost danger has passed.

Your generous 202.0-day season in White 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 White County, IL?

White County is in Zone 6a with an average last frost of April 8. Plan your Radish planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is White County, IL?

White County, Illinois is in USDA Hardiness Zone 6a. The average last spring frost is April 8 and first fall frost is October 27.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help White County gardeners in Zone 6a 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 White County, IL. Local conditions may vary. Last updated: April 2026.