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When to plant Corn in Monona County, IA

Monona County's climate puts the Corn spring window between May 3 and May 24. time plantings around the expected last-frost window for best survival.

When to Plant Corn in Monona County, IA

Corn

Corn is a warm-season grass grown for its sweet ears, which are best eaten soon after harvest. It is wind-pollinated and must be planted in blocks for good kernel fill.

Monona County, Iowa is in USDA Zone 5a. The average last spring frost is April 26 and the first fall frost is October 10, giving you a growing season of approximately 167 days.

At an elevation of 732 feet, Monona County receives approximately 35.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 83°F, so choose short-season varieties of Corn to ensure they mature before fall.

Monona County, IA (Zone 5a) Moderate season
167 days
Last Spring Frost April 26
167 growing days
First Fall Frost October 10

Monona County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-7.1

Drainage

Well Drained

How Much Corn to Grow

1-2 ears
Average yield per plant
15
Plants per person
30 sq ft
Space per person

For a family of 4, plant approximately 60 corn plants in about 120 sq ft. In Monona County's 167-day season, you'll have plenty of time for a full harvest. Plan your garden layout →

Monthly Watering Guide for Corn

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

Month Corn Needs Rainfall You Supplement Action
Jan 1.3" 0" ❄️ Dormant
Feb 1.7" 0" ❄️ Dormant
Mar 2.8" 0" ❄️ Dormant
Apr 4.3" 3" 1.3" 💧 Light watering
May 4.3" 3.8" 0.5" 💧 Light watering
Jun 4.3" 4.3" 0" ✅ Rainfall sufficient
Jul 4.3" 4" 0.3" 💧 Light watering
Aug 4.3" 4.2" 0.1" 💧 Light watering
Sep 4.3" 2.8" 1.5" 💧 Light watering
Oct 4.3" 3" 1.3" 💧 Light watering
Nov 2.2" 0" ❄️ Dormant
Dec 2.2" 0" ❄️ Dormant

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

Corn Planting Timeline — Monona County, IA

Corn Planting Calendar

Activity When Date Range
Direct Sow May 3 May 3 – May 24
Harvest July 5 Jul 5 – Aug 30

Plant 1" deep · 12" apart · Rows 36" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

60–100 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 5a

📆 Growing Season

167 days in Monona County

Growing Tips for Monona County

Plant in blocks of at least 4 rows rather than single rows for proper pollination. Direct sow after soil reaches 60F. Side-dress with nitrogen when plants are knee-high.

Companion Planting

Good Companions

Avoid Planting Near

  • Tomatoes
  • Celery

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Corn in Monona County, IA?

Monona County is in Zone 5a with an average last frost of April 26. Plan your Corn planting based on this frost date — see the calendar above for exact timing.

What planting zone is Monona County, IA?

Monona County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is April 26 and first fall frost is October 10.

When should I plant Corn in Monona County, IA?

In Monona County, IA, plant Corn after the last frost (around April 26) and before the first frost (around October 10). Best results when soil holds above 50°F.

What growing zone is Monona County, IA for Corn?

Monona County sits in USDA Zone 5a. Corn grows reliably in zones 3a through 11b, so it's a good fit here.

Can Corn grow in Monona County's climate?

Yes — Corn grows well in Monona County's temperate climate. Monona County averages a 167-day frost-free season, with last frost around April 26 and first frost around October 10.

🌱

Your Monona County Garden Planner — Free

A 22-page printable planner built for Monona 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.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Monona County, IA. Local conditions may vary. Last updated: August 2026.

Sources & credits

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