Planting Dates for Iowa

Iowa's deep, rich prairie topsoil is legendary — some of the most fertile soil on Earth. The state's continental climate brings warm summers ideal for growing, with adequate rainfall for most crops.

USDA Zones 4b-5b • 140-170 frost-free days depending on location

Frost Dates in Iowa

Average last spring frost and first fall frost dates for Iowa cities. Use these to calculate your planting windows.

CityLast Spring FrostFirst Fall FrostFrost-Free DaysUSDA Zone
Des MoinesApr 22Oct 111725b
Cedar RapidsApr 26Oct 81655a
Sioux CityApr 28Oct 51605a

Gardening Tips for Iowa

  • ✓Iowa's deep topsoil is among the richest in the world for vegetable production.
  • ✓Plan for last frost around May 10-15 in central Iowa.
  • ✓Long summer days (15+ hours) provide excellent growing conditions.
  • ✓Wind protection is important — use hedgerows or fences to shelter gardens.

What to Plant in Iowa

Cold-Hardy Crops (plant early)

These crops tolerate frost and can be planted 2-6 weeks before your last frost date.

LettuceSemi-Hardy

30-60 days from sowing

PeasHardy

55-70 days from sowing

CarrotsSemi-Hardy

60-80 days from sowing

KaleHardy

50-70 days from sowing

BroccoliSemi-Hardy

55-80 days from transplant

SpinachHardy

35-50 days from sowing

RadishesHardy

20-35 days from sowing

GarlicHardy

July-August the following year

OnionsHardy

90-120 days from transplant

PotatoesSemi-Hardy

70-120 days from planting

BeetsSemi-Hardy

50-70 days from sowing

Swiss ChardSemi-Hardy

50-60 days from sowing

Warm-Season Crops (plant after last frost)

Start these indoors and transplant after all frost danger has passed.

TomatoesVery Tender

60-85 days from transplant

PeppersVery Tender

60-90 days from transplant

BeansTender

50-65 days from sowing

CucumbersVery Tender

50-65 days from sowing

Zucchini & Summer SquashTender

45-60 days from sowing

CornTender

60-100 days from sowing

Herbs (Basil, Cilantro, Dill)Tender

30-60 days from sowing

Get Exact Planting Dates for Iowa

Enter your city's frost date and get precise seed starting, transplant, and harvest dates for 38+ vegetables — free.

Frequently Asked Questions

When is the last frost date in Iowa?

Last frost dates in Iowa vary by city: Des Moines (Apr 22), Cedar Rapids (Apr 26), Sioux City (Apr 28).

What USDA hardiness zones are in Iowa?

Iowa spans USDA hardiness zones 4b-5b. Your specific zone determines which perennials survive winter and when to start planting annuals.

What vegetables grow best in Iowa?

Hardy crops like peas, kale, spinach, and garlic thrive across Iowa. In warmer zones, tomatoes, peppers, and cucumbers do well with proper timing. Use our free calculator for exact planting dates.

How long is the growing season in Iowa?

140-170 frost-free days depending on location. Extend your season with cold frames, row covers, and indoor seed starting.

Planting Dates by State

Explore More Resources