Cedar Rapids, IA Frost Dates & Growing Season

The two dates every Cedar Rapids garden is planned around, plus ready-computed planting windows for the most popular crops.

Last spring frost
Apr 28
~50% chance of frost after
First fall frost
Oct 12
~50% chance of frost before
Growing season
167 days
frost-free stretch
USDA zone
5b
2023 hardiness map
Risky (1 year in 10)MedianSafe (9 years in 10)
Last spring frost Apr 14 Apr 28 May 13
First fall frost Oct 25 Oct 12 Sep 29
Hard freeze (28°F), median last Apr 17 · first Oct 22

Computed from NOAA 1991–2020 climate normals at the Cedar Rapids #1 station (10 km from central Cedar Rapids). "Safe" means frost past that date happens only about one year in ten. Your exact garden can still run days either way with elevation and terrain — check your own ZIP with the frost date lookup.

Planting windows for Cedar Rapids

Computed from Cedar Rapids's own frost dates. Click any crop for the full zone-5 growing guide — varieties, spacing, fall plantings, and more.

CropStart seeds indoorsTransplantDirect sow
🍅 Tomatoes Mar 3 – Mar 17 May 5 – May 12
🫑 Peppers Feb 17 – Mar 3 May 12 – May 19
🥬 Lettuce Mar 17 – Mar 31 Mar 31 – Apr 14 Mar 31 – Apr 28
🫛 Peas Mar 17 – Mar 31
🥕 Carrots Apr 7 – Apr 28
🥦 Broccoli Mar 10 – Mar 24 Apr 7 – Apr 21
🥬 Kale Mar 17 – Mar 31 Mar 31 – Apr 14 Mar 31 – Apr 14
🥒 Cucumbers Mar 31 – Apr 7 May 5 – May 12 May 5 – May 12
🥒 Zucchini Mar 31 – Apr 7 May 5 – May 12 May 5 – May 12
🫘 Green Beans (Bush) May 5 – May 12
🌽 Sweet Corn May 5 – May 12
🌿 Basil Mar 17 – Mar 31 May 5 – May 12 May 12 – May 19
🧄 Garlic Fall: Aug 31 – Sep 28

Want this for all 50 crops, or as a printable seed-shelf schedule? Use the planting calendar and the seed starting scheduler — both can use Cedar Rapids's dates automatically after a lookup.

Reading the season in Cedar Rapids

Roughly 167 frost-free days gives Cedar Rapids gardeners room for nearly every common vegetable. Warm-season crops go out after Apr 28; a fall garden sown in late summer matures comfortably before the Oct 12 frost.

Frequently asked questions

When is the last frost in Cedar Rapids, IA?

The average last spring frost in Cedar Rapids is around Apr 28, based on 1991–2020 climate normals. That's a median — about half of years see a later frost, so tender crops are safest going out a week or two after this date.

When is the first frost in Cedar Rapids, IA?

The average first fall frost in Cedar Rapids arrives around Oct 12. Crops still in the garden need to mature before then, and frost-tender plants need harvesting or protection as the date approaches.

How long is the growing season in Cedar Rapids?

About 167 frost-free days on average, from Apr 28 to Oct 12. That fits nearly all common vegetables, though the longest-season melons and sweet potatoes benefit from transplants.

What USDA zone is Cedar Rapids in?

USDA zone 5b on the 2023 Plant Hardiness Zone Map. Note that zones describe winter cold, not frost timing — these frost dates are the numbers to plan plantings around.