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When to plant Lettuce in Warren County, IA

Plant Lettuce in Warren County after April 26; the prime window is April 12–May 3. A second sowing from July 31 to August 14 extends the harvest into fall.

When to Plant Lettuce in Warren County, IA

Lettuce

Lettuce is a fast-growing cool-season green available in leaf, romaine, butterhead, and crisphead types. It is the foundation of salads and one of the easiest crops to grow.

Warren County, Iowa is in USDA Zone 5b. The average last spring frost is April 26 and the first fall frost is October 9, giving you a growing season of approximately 166 days.

At an elevation of 853 feet, Warren County receives approximately 30.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Lettuce during the growing season.

Warren County, IA (Zone 5b) Moderate season
166 days
Last Spring Frost April 26
166 growing days
First Fall Frost October 9

Warren County Soil Profile

Soil Type

Silt Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Lettuce Planting Timeline — Warren County, IA

Lettuce Planting Calendar

Activity When Date Range
Start Indoors March 22 Mar 22 – Apr 5
Transplant Outdoors April 26 Apr 26 – May 10
Direct Sow April 12 Apr 12 – May 3
Harvest May 31 May 31 – Aug 9
Fall Sowing July 31 Jul 31 – Aug 14

Plant 0.5" deep · 6" apart · Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Partial Shade (3-6 hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

30–60 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 5b

📆 Growing Season

166 days in Warren County

Growing Tips for Warren County

Sow seeds directly every 2 weeks for continuous harvest. Provide afternoon shade in warm weather to delay bolting. Harvest in the morning for crispest leaves.

Companion Planting

Good Companions

Avoid Planting Near

  • Celery

Check more plant combinations with our Companion Planting Checker →

🌾 Save Your Own Lettuce Seeds
Life Cycle Annual
Pollination Self-Pollinating
How to Collect Let plants bolt and flower. Harvest seed heads when fluffy.
Storage Store airtight; viable 6 years at 35°F, under 45% humidity.

Very easy to save. Let a few plants bolt each season.

Frequently Asked Questions

When should I plant Lettuce in Warren County, IA?

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

What planting zone is Warren County, IA?

Warren County, Iowa is in USDA Hardiness Zone 5b. The average last spring frost is April 26 and first fall frost is October 9.

When should I plant Lettuce in Warren County, IA?

In Warren County, IA, plant Lettuce after the last frost (around April 26) and before the first frost (around October 9). Best results when soil holds above 50°F.

What growing zone is Warren County, IA for Lettuce?

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

Can Lettuce grow in Warren County's climate?

Yes — Lettuce grows well in Warren County's temperate climate. Warren County averages a 166-day frost-free season, with last frost around April 26 and first frost around October 9.

🌱

Your Warren County Garden Planner — Free

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

Sources & credits

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