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When to plant Napa Cabbage in Dubuque County, IA

Plant Napa Cabbage in Dubuque County after April 29; the prime window is April 15–May 6. A second sowing from July 31 to August 14 extends the harvest into fall.

When to Plant Napa Cabbage in Dubuque County, IA

Napa cabbage forms tall, barrel-shaped heads with tender, crinkled leaves and a mild, slightly sweet flavor. It is the primary cabbage used for kimchi.

Dubuque County, Iowa is in USDA Zone 5a. The average last spring frost is April 29 and the first fall frost is October 9, giving you a growing season of approximately 163 days.

At an elevation of 1,243 feet, Dubuque County receives approximately 36.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Napa Cabbage to ensure they mature before fall.

Dubuque County, IA (Zone 5a) Moderate season
163 days
Last Spring Frost April 29
163 growing days
First Fall Frost October 9

Dubuque County Soil Profile

Soil Type

Silt Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Napa Cabbage Planting Timeline — Dubuque County, IA

Napa Cabbage Planting Calendar

Activity When Date Range
Start Indoors March 25 Mar 25 – Apr 8
Transplant Outdoors April 29 Apr 29 – May 13
Direct Sow April 15 Apr 15 – May 6
Harvest June 24 Jun 24 – Jul 29
Fall Sowing July 31 Jul 31 – Aug 14

Plant 1" deep · 15" apart · Rows 24" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

High — keep soil consistently moist

📅 Days to Maturity

55–75 days

🧪 Soil pH

Needs 6–7.5 · Your soil: N/A

🗺️ USDA Zone

Zone 5a

📆 Growing Season

163 days in Dubuque County

Growing Tips for Dubuque County

Best grown as a fall crop. Direct sow in late summer, 60-70 days before first frost. Keep soil evenly moist. Bolt-resistant varieties are available for spring planting.

Companion Planting

Good Companions

Avoid Planting Near

  • Strawberries

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Napa Cabbage in Dubuque County, IA?

Dubuque County is in Zone 5a with an average last frost of April 29. Plan your Napa Cabbage planting based on this frost date — see the calendar above for exact timing.

What planting zone is Dubuque County, IA?

Dubuque County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is April 29 and first fall frost is October 9.

When should I plant Napa Cabbage in Dubuque County, IA?

In Dubuque County, IA, plant Napa Cabbage after the last frost (around April 29) and before the first frost (around October 9). Best results when soil holds above 50°F.

What growing zone is Dubuque County, IA for Napa Cabbage?

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

Can Napa Cabbage grow in Dubuque County's climate?

Yes — Napa Cabbage grows well in Dubuque County's temperate climate. Dubuque County averages a 163-day frost-free season, with last frost around April 29 and first frost around October 9.

🌱

Your Dubuque County Garden Planner — Free

A 22-page printable planner built for Dubuque 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 Dubuque County, IA. Local conditions may vary. Last updated: June 2026.

Sources & credits

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