Oelwein 2 S, IA Frost Dates & Growing Season

The two dates every Oelwein 2 S garden is planned around, plus ready-computed planting windows for the most popular crops.

Last spring frost
Apr 30
~50% chance of frost after
First fall frost
Oct 9
~50% chance of frost before
Growing season
162 days
frost-free stretch
USDA zone
≈ 5b
estimated from nearby reference
Risky (1 year in 10)MedianSafe (9 years in 10)
Last spring frost Apr 14 Apr 30 May 13
First fall frost Oct 20 Oct 9 Sep 26
Hard freeze (28°F), median last Apr 19 · first Oct 19

Computed from NOAA 1991–2020 climate normals at the OELWEIN 2 S station. "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 Oelwein 2 S

Computed from Oelwein 2 S'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 5 – Mar 19 May 7 – May 14
🫑 Peppers Feb 19 – Mar 5 May 14 – May 21
🥬 Lettuce Mar 19 – Apr 2 Apr 2 – Apr 16 Apr 2 – Apr 30
🫛 Peas Mar 19 – Apr 2
🥕 Carrots Apr 9 – Apr 30
🥦 Broccoli Mar 12 – Mar 26 Apr 9 – Apr 23
🥬 Kale Mar 19 – Apr 2 Apr 2 – Apr 16 Apr 2 – Apr 16
🥒 Cucumbers Apr 2 – Apr 9 May 7 – May 14 May 7 – May 14
🥒 Zucchini Apr 2 – Apr 9 May 7 – May 14 May 7 – May 14
🫘 Green Beans (Bush) May 7 – May 14
🌽 Sweet Corn May 7 – May 14
🌿 Basil Mar 19 – Apr 2 May 7 – May 14 May 14 – May 21
🧄 Garlic Fall: Aug 28 – Sep 25

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 Oelwein 2 S's dates automatically after a lookup.

Reading the season in Oelwein 2 S

Roughly 162 frost-free days gives Oelwein 2 S gardeners room for nearly every common vegetable. Warm-season crops go out after Apr 30; a fall garden sown in late summer matures comfortably before the Oct 9 frost.

Frequently asked questions

When is the last frost in Oelwein 2 S, IA?

The average last spring frost in Oelwein 2 S is around Apr 30, 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 Oelwein 2 S, IA?

The average first fall frost in Oelwein 2 S arrives around Oct 9. 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 Oelwein 2 S?

About 162 frost-free days on average, from Apr 30 to Oct 9. That fits nearly all common vegetables, though the longest-season melons and sweet potatoes benefit from transplants.

What USDA zone is Oelwein 2 S 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.