Cool-Season Vegetable

When to Plant Lettuce in Iowa

Fast-growing and forgiving. Plant in spring and fall for a nearly year-round supply of fresh salad greens.

The Short Answer

Lettuce are cold-tolerant and do well in Iowa's humid climate. You can direct sow 4 weeks before your last frost — that's as early as May 5 - May 20 in Northern Iowa. Iowa gardeners can also plant a fall crop. Outstanding black prairie soils. Some of the richest agricultural land in the world. Minimal...

Iowa Frost Dates

Your planting dates depend on which part of Iowa you're in. Here are the frost date ranges by region:

Region Zones Last Frost (Spring) First Frost (Fall)
Northern Iowa 4b, 5a May 5 - May 20 Sep 20 - Oct 5
Central Iowa 5a, 5b Apr 25 - May 10 Oct 1 - Oct 15
Southern Iowa 5b Apr 20 - May 5 Oct 5 - Oct 20

Lettuce Planting Schedule for Iowa

Northern Iowa (Zones 4b, 5a)

Average last frost: May 5 - May 20 · Average first frost: Sep 20 - Oct 5

Start Seeds Indoors
4 wks before frost
Transplant Outside
2 wks before frost
Direct Sow
4 wks before frost
Fall Planting
8 wks before first frost

Central Iowa (Zones 5a, 5b)

Average last frost: Apr 25 - May 10 · Average first frost: Oct 1 - Oct 15

Start Seeds Indoors
4 wks before frost
Transplant Outside
2 wks before frost
Direct Sow
4 wks before frost
Fall Planting
8 wks before first frost

Southern Iowa (Zones 5b)

Average last frost: Apr 20 - May 5 · Average first frost: Oct 5 - Oct 20

Start Seeds Indoors
4 wks before frost
Transplant Outside
2 wks before frost
Direct Sow
4 wks before frost
Fall Planting
8 wks before first frost

Growing Lettuce in Iowa

Lettuce in Iowa's Climate

Your cool climate is actually excellent for lettuce — the crop thrives in 55-70°F conditions that you have for months. Direct sow as soon as soil thaws in spring and continue harvesting well into summer because your moderate temperatures delay bolting far longer than in southern states. Fall lettuce is equally productive. In the coldest zones, cold frames extend harvest into December.

Soil Considerations for Iowa

Outstanding black prairie soils. Some of the richest agricultural land in the world. Minimal amendment needed.

Iowa Climate & Growing Season

Continental climate. Cold winters, warm humid summers. Good growing season with adequate rainfall.

Growing season length varies across Iowa: Northern Iowa (4b, 5a) has a last frost around May 5 - May 20, while Southern Iowa (5b) sees frost end around Apr 20 - May 5. This difference matters for lettuce — adjust your planting dates to match your specific region.

Growing Tips

Succession plant every 2-3 weeks for continuous harvest. Shade cloth extends the season into warmer months.

Companion Planting

Plant lettuce alongside these companions for better growth:

Carrots Radishes Strawberries Chives

The Bottom Line

Lettuce can be grown successfully across Iowa, but your exact planting dates depend on which region you're in. Northern Iowa gardeners should plan around a May 5 - May 20 last frost, while those in Southern Iowa can typically plant earlier. For exact dates based on your zip code, use our free planting date finder.

Related Guides

Lettuce Growing Guide National planting guide with all states Iowa Planting Calendar All plants for Iowa Lettuce in Alabama Alabama planting dates Lettuce in Alaska Alaska planting dates Lettuce in Arizona Arizona planting dates Lettuce in Arkansas Arkansas planting dates
Note: All dates are based on NOAA 30-year Climate Normals and represent historical averages, not predictions for any specific year. Always check your local weather forecast before planting frost-sensitive crops. Learn about our data sources.

Last reviewed: March 29, 2026

Ready to Start Planting?

Enter your zip code and pick your plant. We'll tell you exactly when to plant, start seeds, and harvest — based on where you live.

Find Your Planting Dates