Rockford, IL Frost Dates & Growing Season

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

Last spring frost
Apr 24
~50% chance of frost after
First fall frost
Oct 17
~50% chance of frost before
Growing season
176 days
frost-free stretch
USDA zone
5b
2023 hardiness map
Risky (1 year in 10)MedianSafe (9 years in 10)
Last spring frost Apr 10 Apr 24 May 8
First fall frost Oct 30 Oct 17 Oct 2
Hard freeze (28°F), median last Apr 13 · first Oct 28

Computed from NOAA 1991–2020 climate normals at the Rockford Gtr Rockford Airport station (9 km from central Rockford). "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 Rockford

Computed from Rockford'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 Feb 27 – Mar 13 May 1 – May 8
🫑 Peppers Feb 13 – Feb 27 May 8 – May 15
🥬 Lettuce Mar 13 – Mar 27 Mar 27 – Apr 10 Mar 27 – Apr 24
🫛 Peas Mar 13 – Mar 27
🥕 Carrots Apr 3 – Apr 24
🥦 Broccoli Mar 6 – Mar 20 Apr 3 – Apr 17
🥬 Kale Mar 13 – Mar 27 Mar 27 – Apr 10 Mar 27 – Apr 10
🥒 Cucumbers Mar 27 – Apr 3 May 1 – May 8 May 1 – May 8
🥒 Zucchini Mar 27 – Apr 3 May 1 – May 8 May 1 – May 8
🫘 Green Beans (Bush) May 1 – May 8
🌽 Sweet Corn May 1 – May 8
🌿 Basil Mar 13 – Mar 27 May 1 – May 8 May 8 – May 15
🧄 Garlic Fall: Sep 5 – Oct 3

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 Rockford's dates automatically after a lookup.

Reading the season in Rockford

Roughly 176 frost-free days gives Rockford gardeners room for nearly every common vegetable. Warm-season crops go out after Apr 24; a fall garden sown in late summer matures comfortably before the Oct 17 frost.

Frequently asked questions

When is the last frost in Rockford, IL?

The average last spring frost in Rockford is around Apr 24, 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 Rockford, IL?

The average first fall frost in Rockford arrives around Oct 17. 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 Rockford?

About 176 frost-free days on average, from Apr 24 to Oct 17. That fits nearly all common vegetables, though the longest-season melons and sweet potatoes benefit from transplants.

What USDA zone is Rockford 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.