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When to plant Radish in Cook County, MN

Cook County's climate puts the Radish spring window between May 13 and June 3. be cautious and check the 10-day forecast before planting tender crops. A second sowing from July 7 to July 21 extends the harvest into fall.

When to Plant Radish in Cook County, MN

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.

Cook County, Minnesota is in USDA Zone 3b. The average last spring frost is May 20 and the first fall frost is September 29, giving you a growing season of approximately 132 days.

At an elevation of 1,068 feet, Cook County receives approximately 34.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 80°F, so choose short-season varieties of Radish to ensure they mature before fall.

Cook County, MN (Zone 3b) Short season
132 days
Last Spring Frost May 20
132 growing days
First Fall Frost September 29

Cook County Soil Profile

Soil Type

Silt Loam

Soil pH

6.1-7.1

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 1.4" 0" ❄️ Dormant
Feb 1.6" 0" ❄️ Dormant
Mar 2.5" 0" ❄️ Dormant
Apr 3.5" 0" ❄️ Dormant
May 4.3" 3.4" 0.9" 💧 Light watering
Jun 4.3" 4.7" 0" ✅ Rainfall sufficient
Jul 4.3" 3.9" 0.4" 💧 Light watering
Aug 4.3" 3" 1.3" 💧 Light watering
Sep 4.3" 3.2" 1.1" 💧 Light watering
Oct 2.7" 0" ❄️ Dormant
Nov 2.5" 0" ❄️ Dormant
Dec 2" 0" ❄️ Dormant

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

Radish Planting Timeline — Cook County, MN

Radish Planting Calendar

Activity When Date Range
Direct Sow May 13 May 13 – Jun 3
Harvest June 10 Jun 10 – Jul 1
Fall Sowing July 7 Jul 7 – Jul 21

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

Month-by-Month Timeline

MonthActivities
January
February
March
April
May Direct Sow
June Direct Sow Harvest
July Fall Sowing Harvest
August
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 3b

📆 Growing Season

132 days in Cook County

Growing Tips for Cook 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 Cook County, MN?

Cook County is in Zone 3b with an average last frost of May 20. Plan your Radish planting based on this frost date — see the calendar above for exact timing.

What planting zone is Cook County, MN?

Cook County, Minnesota is in USDA Hardiness Zone 3b. The average last spring frost is May 20 and first fall frost is September 29.

When should I plant Radish in Cook County, MN?

In Cook County, MN, plant Radish after the last frost (around May 20) and before the first frost (around September 29). Best results when soil holds above 50°F.

What growing zone is Cook County, MN for Radish?

Cook County sits in USDA Zone 3b. Radish grows reliably in zones 2a through 11b, so it's a good fit here.

Can Radish grow in Cook County's climate?

Yes — Radish grows well in Cook County's temperate climate. Cook County averages a 132-day frost-free season, with last frost around May 20 and first frost around September 29.

🌱

Your Cook County Garden Planner — Free

A 22-page printable planner built for Cook County (Zone 3b). 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 Cook County, MN. Local conditions may vary. Last updated: July 2026.

Sources & credits

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