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When to plant Basil in Dubuque County, IA

Plant Basil in Dubuque County, when soil hits 50°F — usually May 6. Continue planting through May 27 for the spring crop.

When to Plant Basil in Dubuque County, IA

Basil
Dubuque County, Iowa Zone 5a July

This month in Dubuque County, Iowa

July rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Dubuque County, Iowa.

Avg. last frost April 29
Avg. first frost October 9
Soil temp (4") 72°F
Watering Low
Pest pressure High
Daylight 14.8 hrs
  1. It's harvest week for basil

    Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.

Coming up in August — start thinking about
  • First harvests: basil

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Basil is a fragrant warm-season herb essential to Italian and Thai cuisines. It comes in many varieties including sweet, Thai, purple, and lemon types.

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 Basil 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

5.8-7.3

Drainage

Well Drained

Monthly Watering Guide for Basil

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

Month Basil Needs Rainfall You Supplement Action
Jan 1.4" 0" ❄️ Dormant
Feb 1.6" 0" ❄️ Dormant
Mar 2.4" 0" ❄️ Dormant
Apr 4.3" 3.4" 0.9" 💧 Light watering
May 4.3" 4.1" 0.2" 💧 Light watering
Jun 4.3" 4.8" 0" ✅ Rainfall sufficient
Jul 4.3" 4.3" 0" ✅ Rainfall sufficient
Aug 4.3" 3.5" 0.8" 💧 Light watering
Sep 4.3" 3.2" 1.1" 💧 Light watering
Oct 4.3" 3.3" 1" 💧 Light watering
Nov 2.6" 0" ❄️ Dormant
Dec 1.9" 0" ❄️ Dormant

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

Basil Planting Timeline — Dubuque County, IA

Basil Planting Calendar

Activity When Date Range
Start Indoors March 11 Mar 11 – Mar 25
Transplant Outdoors May 13 May 13 – May 27
Direct Sow May 6 May 6 – May 27
Harvest July 8 Jul 8 – Sep 9

Plant 0.5" deep · 8" apart · Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

50–75 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 5a

📆 Growing Season

163 days in Dubuque County

Growing Tips for Dubuque County

Start seeds indoors or direct sow after last frost. Pinch flower buds to extend leaf production. Harvest leaves from the top down, cutting just above a leaf pair.

Companion Planting

Good Companions

Avoid Planting Near

  • Rue
  • Sage

Check more plant combinations with our Companion Planting Checker →

🌾 Save Your Own Basil Seeds
Life Cycle Annual
Pollination Self-Pollinating
How to Collect Let flower spikes dry brown on the plant.
Storage Store airtight; viable 5 years at 35°F, under 45% humidity.

Isolate 150 ft between varieties. Different basil species can cross.

Frequently Asked Questions

When should I plant Basil in Dubuque County, IA?

Dubuque County is in Zone 5a with an average last frost of April 29. Plan your Basil 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 Basil in Dubuque County, IA?

In Dubuque County, IA, plant Basil 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 Basil?

Dubuque County sits in USDA Zone 5a. Basil grows reliably in zones 4a through 11b, so it's a good fit here.

Can Basil grow in Dubuque County's climate?

Yes — Basil 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: July 2026.

Sources & credits

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