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When to Plant Radish in Clinton County, MO

Clinton County, Missouri Zone 6a May

Your May planting checklist for Clinton County, Missouri

Your Clinton County, Missouri garden is entering a new phase. Here's what's on the schedule for May and why each task matters now.

Avg. last frost April 13
Avg. first frost October 25
Soil temp (4") 60°F
Watering Low
Pest pressure Low
Daylight 14.2 hrs
  1. Collect radish at their peak

    This is the payoff month. Bring a basket, bring a friend, and get into the beds.

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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.

Clinton County, Missouri is in USDA Zone 6a. The average last spring frost is April 13 and the first fall frost is October 25, giving you a growing season of approximately 195 days.

At an elevation of 525 feet, Clinton County receives approximately 36.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Radish to ensure they mature before fall.

Clinton County, MO (Zone 6a) Moderate season
195 days
Last Spring Frost April 13
195 growing days
First Fall Frost October 25

Clinton County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-7.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (147 days to spare)
Transplant: Apr 4 🍅 Harvest: May 2 – May 23
Recommended (50%) ✓ Fits season (146 days to spare)
Transplant: Apr 13 🍅 Harvest: May 11 – Jun 1
Safe Start (90%) ✓ Fits season (148 days to spare)
Transplant: Apr 26 🍅 Harvest: May 24 – Jun 14

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 Clinton County

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

Soil pH

Your soil pH (5.5–7.1) overlaps with Radish's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.6%). 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

11
successive plantings in your 195-day season

Sow every 2.4 weeks. Last sowing by Sep 20 to harvest before frost.

For a dedicated fall crop, sow by Aug 16.

Plant Water Budget

Plant needs
0.5″/week
Rainfall provides
0.8″/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 1.6" 0" ❄️ Dormant
Feb 1.6" 0" ❄️ Dormant
Mar 2.4" 0" ❄️ Dormant
Apr 2.2" 3.2" 0" ✅ Rainfall sufficient
May 2.2" 4.9" 0" ✅ Rainfall sufficient
Jun 2.2" 4.5" 0" ✅ Rainfall sufficient
Jul 2.2" 3.9" 0" ✅ Rainfall sufficient
Aug 2.2" 3.4" 0" ✅ Rainfall sufficient
Sep 2.2" 3.6" 0" ✅ Rainfall sufficient
Oct 2.2" 3.3" 0" ✅ Rainfall sufficient
Nov 2.4" 0" ❄️ Dormant
Dec 1.9" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Clinton County). Supplement amounts are based on average rainfall — 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" — 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.

Radish needs ~349 GDD — county provides 2,388 GDD Excellent fit

Radish Planting Timeline — Clinton County, MO

Radish Planting Calendar

Activity When Date Range
Direct Sow March 30 Mar 30 – Apr 20
Harvest April 27 Apr 27 – May 18
Fall Sowing August 16 Aug 16 – Aug 30

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.5"/week · Natural rainfall sufficient

📅 Days to Maturity

22–35 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 6a

📆 Growing Season

195 days in Clinton County

Growing Tips for Radish in Clinton County

Direct sow Radish outdoors after April 13 in Clinton County when soil has warmed and frost danger has passed.

Your generous 195.0-day season in Clinton 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 Clinton County, MO?

Clinton County is in Zone 6a with an average last frost of April 13. Plan your Radish planting based on this frost date — see the calendar above for exact timing.

What planting zone is Clinton County, MO?

Clinton County, Missouri is in USDA Hardiness Zone 6a. The average last spring frost is April 13 and first fall frost is October 25.

🌱

Your Clinton County Garden Planner — Free

A 24-page printable planner built for Clinton County (Zone 6a). 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 Clinton County, MO. 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.