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When to plant Radish in Allamakee County, IA

Aim to plant Radish in Allamakee County on or after April 18; the window stays open through May 9. Allamakee County's 158-day frost-free season gives you a single solid spring crop with a brief fall option. A second sowing from July 29 to August 12 extends the harvest into fall.

When to Plant Radish in Allamakee County, IA

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.

Allamakee County, Iowa is in USDA Zone 5a. The average last spring frost is May 2 and the first fall frost is October 7, giving you a growing season of approximately 158 days.

At an elevation of 804 feet, Allamakee County receives approximately 39.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 82°F, so choose short-season varieties of Radish to ensure they mature before fall.

Allamakee County, IA (Zone 5a) Moderate season
158 days
Last Spring Frost May 2
158 growing days
First Fall Frost October 7

Allamakee County Soil Profile

Soil Type

Silt Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Radish Planting Timeline — Allamakee County, IA

Radish Planting Calendar

Activity When Date Range
Direct Sow April 18 Apr 18 – May 9
Harvest May 16 May 16 – Jun 6
Fall Sowing July 29 Jul 29 – Aug 12

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

Month-by-Month Timeline

MonthActivities
January
February
March
April Direct Sow
May Direct Sow Harvest
June Harvest
July Fall Sowing
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 5a

📆 Growing Season

158 days in Allamakee County

Growing Tips for Allamakee 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 Allamakee County, IA?

Allamakee County is in Zone 5a with an average last frost of May 2. Plan your Radish planting based on this frost date — see the calendar above for exact timing.

What planting zone is Allamakee County, IA?

Allamakee County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is May 2 and first fall frost is October 7.

When should I plant Radish in Allamakee County, IA?

In Allamakee County, IA, plant Radish after the last frost (around May 2) and before the first frost (around October 7). Best results when soil holds above 50°F.

What growing zone is Allamakee County, IA for Radish?

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

Can Radish grow in Allamakee County's climate?

Yes — Radish grows well in Allamakee County's temperate climate. Allamakee County averages a 158-day frost-free season, with last frost around May 2 and first frost around October 7.

🌱

Your Allamakee County Garden Planner — Free

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

Sources & credits

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