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When to plant Radish in Marshall County, IL

Marshall County's spring Radish window runs April 7 through April 28. time plantings around the expected last-frost window for best survival. A second sowing from August 4 to August 18 extends the harvest into fall.

When to Plant Radish in Marshall 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.

Marshall County, Illinois is in USDA Zone 5b. The average last spring frost is April 21 and the first fall frost is October 13, giving you a growing season of approximately 175 days.

At an elevation of 1,177 feet, Marshall County receives approximately 30.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Radish to ensure they mature before fall.

Marshall County, IL (Zone 5b) Moderate season
175 days
Last Spring Frost April 21
175 growing days
First Fall Frost October 13

Marshall County Soil Profile

Soil Type

Silt Loam

Soil pH

6-6.8

Drainage

Well Drained

Monthly Watering Guide for Radish

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

Month Radish Needs Rainfall You Supplement Action
Jan 1.3" 0" ❄️ Dormant
Feb 1.3" 0" ❄️ Dormant
Mar 2.3" 0" ❄️ Dormant
Apr 4.3" 2.8" 1.5" 💧 Light watering
May 4.3" 3.4" 0.9" 💧 Light watering
Jun 4.3" 4" 0.3" 💧 Light watering
Jul 4.3" 3" 1.3" 💧 Light watering
Aug 4.3" 3.4" 0.9" 💧 Light watering
Sep 4.3" 2.7" 1.6" 💧 Light watering
Oct 4.3" 2.5" 1.8" 💧 Light watering
Nov 2" 0" ❄️ Dormant
Dec 1.7" 0" ❄️ Dormant

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

Radish Planting Timeline — Marshall County, IL

Radish Planting Calendar

Activity When Date Range
Direct Sow April 7 Apr 7 – Apr 28
Harvest May 5 May 5 – May 26
Fall Sowing August 4 Aug 4 – Aug 18

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

22–35 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 5b

📆 Growing Season

175 days in Marshall County

Growing Tips for Marshall County

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 Marshall County, IL?

Marshall County is in Zone 5b with an average last frost of April 21. Plan your Radish planting based on this frost date — see the calendar above for exact timing.

What planting zone is Marshall County, IL?

Marshall County, Illinois is in USDA Hardiness Zone 5b. The average last spring frost is April 21 and first fall frost is October 13.

When should I plant Radish in Marshall County, IL?

In Marshall County, IL, plant Radish after the last frost (around April 21) and before the first frost (around October 13). Best results when soil holds above 50°F.

What growing zone is Marshall County, IL for Radish?

Marshall County sits in USDA Zone 5b. Radish grows reliably in zones 2a through 11b, so it's a good fit here.

Can Radish grow in Marshall County's climate?

Yes — Radish grows well in Marshall County's temperate climate. Marshall County averages a 175-day frost-free season, with last frost around April 21 and first frost around October 13.

🌱

Your Marshall County Garden Planner — Free

A 22-page printable planner built for Marshall County (Zone 5b). 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 Marshall County, IL. Local conditions may vary. Last updated: June 2026.

Sources & credits

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