Little Sioux 2 NW, IA Frost Dates & Growing Season

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

Last spring frost
May 1
~50% chance of frost after
First fall frost
Oct 3
~50% chance of frost before
Growing season
155 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 May 1 May 12
First fall frost Oct 17 Oct 3 Sep 20
Hard freeze (28°F), median last Apr 22 · first Oct 14

Computed from NOAA 1991–2020 climate normals at the LITTLE SIOUX 2 NW 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 Little Sioux 2 NW

Computed from Little Sioux 2 NW'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 6 – Mar 20 May 8 – May 15
🫑 Peppers Feb 20 – Mar 6 May 15 – May 22
🥬 Lettuce Mar 20 – Apr 3 Apr 3 – Apr 17 Apr 3 – May 1
🫛 Peas Mar 20 – Apr 3
🥕 Carrots Apr 10 – May 1
🥦 Broccoli Mar 13 – Mar 27 Apr 10 – Apr 24
🥬 Kale Mar 20 – Apr 3 Apr 3 – Apr 17 Apr 3 – Apr 17
🥒 Cucumbers Apr 3 – Apr 10 May 8 – May 15 May 8 – May 15
🥒 Zucchini Apr 3 – Apr 10 May 8 – May 15 May 8 – May 15
🫘 Green Beans (Bush) May 8 – May 15
🌽 Sweet Corn May 8 – May 15
🌿 Basil Mar 20 – Apr 3 May 8 – May 15 May 15 – May 22
🧄 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 Little Sioux 2 NW's dates automatically after a lookup.

Reading the season in Little Sioux 2 NW

Roughly 155 frost-free days gives Little Sioux 2 NW gardeners room for nearly every common vegetable. Warm-season crops go out after May 1; a fall garden sown in late summer matures comfortably before the Oct 3 frost.

Frequently asked questions

When is the last frost in Little Sioux 2 NW, IA?

The average last spring frost in Little Sioux 2 NW is around May 1, 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 Little Sioux 2 NW, IA?

The average first fall frost in Little Sioux 2 NW 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 Little Sioux 2 NW?

About 155 frost-free days on average, from May 1 to Oct 3. That fits nearly all common vegetables, though the longest-season melons and sweet potatoes benefit from transplants.

What USDA zone is Little Sioux 2 NW 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.