Sioux Ctr 2 SE, IA Frost Dates & Growing Season

The two dates every Sioux Ctr 2 SE 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 3
~50% chance of frost before
Growing season
156 days
frost-free stretch
USDA zone
≈ 5a
estimated from nearby reference
Risky (1 year in 10)MedianSafe (9 years in 10)
Last spring frost Apr 17 Apr 30 May 12
First fall frost Oct 18 Oct 3 Sep 19
Hard freeze (28°F), median last Apr 21 · first Oct 14

Computed from NOAA 1991–2020 climate normals at the SIOUX CTR 2 SE 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 Sioux Ctr 2 SE

Computed from Sioux Ctr 2 SE'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 22 – Sep 19

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 Sioux Ctr 2 SE's dates automatically after a lookup.

Reading the season in Sioux Ctr 2 SE

Roughly 156 frost-free days gives Sioux Ctr 2 SE 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 3 frost.

Frequently asked questions

When is the last frost in Sioux Ctr 2 SE, IA?

The average last spring frost in Sioux Ctr 2 SE 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 Sioux Ctr 2 SE, IA?

The average first fall frost in Sioux Ctr 2 SE arrives around Oct 3. 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 Sioux Ctr 2 SE?

About 156 frost-free days on average, from Apr 30 to Oct 3. That fits nearly all common vegetables, though the longest-season melons and sweet potatoes benefit from transplants.

What USDA zone is Sioux Ctr 2 SE in?

USDA zone 5a 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.