Frost dates · USDA zone 5b
Frost dates for Rockford, IL
Rockford, IL sees its last 32 °F night of spring around April 24 and its first of fall around October 17 — a 174-day freeze-free season in a typical year.
Pick a sauce; the Plan Builder runs this station's dates and hands back the calendar, plant count and gear list.
Freeze odds, by date
| Odds | Last spring freeze after | First fall freeze before |
|---|---|---|
| 9 years in 10 | Apr 10 | Oct 30 |
| Median — 1 year in 2 | Apr 24 | Oct 17 |
| 1 year in 10 | May 8 | Oct 2 |
The top row is the risky edge: in 9 years of 10 a spring freeze still comes after it, so tender transplants set out then need cover. The bottom row is the cautious date — only 1 year in 10 freezes after it — and the one to plan uncovered tender transplants against. Freeze-free season: 174 days median, at least 154 in 9 years of 10, at least 192 days in 1 year of 10. NOAA ranks season length year by year, so it is not the gap between two rows above. A hard freeze (28 °F) has a median last date of Apr 13 and first of Oct 28.
Rockford planting calendar, 2027
Every row runs from the median last frost (Apr 24) and median first frost (Oct 17) above, using each cultivar's days to maturity. Same engine as the Plan Builder.
| Crop | Start indoors | Transplant / plant | First harvest | Days |
|---|---|---|---|---|
| Hardneck GarlicSiberian (porcelain hardneck) | — | Oct 15prior fall | Jun 12 | 240 from sow |
| Spanish OnionYellow Sweet Spanish (long-day) | Jan 30 | Mar 27 | Jul 15 | 110 from transplant |
| Mustard greensGarnet Giant (Brassica juncea) | Direct sow | Apr 24 | May 24 | 30 from sow |
| CilantroSlow Bolt (Coriandrum sativum) | Apr 10 | Apr 10 | May 25 | 45 from sow |
| Genovese BasilGenovese | Mar 27 | May 8 | Jul 7 | 60 from transplant |
| CayenneLong Slim Cayenne (Capsicum annuum) | Feb 27 | May 1 | Jul 15 | 75 from transplant |
| HabaneroOrange Habanero (Capsicum chinense) | Feb 13 | May 8 | Aug 11 | 95 from transplant |
| JalapeñoEarly Jalapeño (Capsicum annuum) | Feb 27 | May 1 | Jul 15 | 75 from transplant |
| Marconi Red PepperMarconi Red (Capsicum annuum) | Feb 27 | May 1 | Jul 20 | 80 from transplant |
| SerranoSerrano Tampiqueño (Capsicum annuum) | Feb 27 | May 1 | Jul 20 | 80 from transplant |
| Nantes CarrotScarlet Nantes | Apr 10 | Apr 10 | Jun 19 | 70 from sow |
| TomatilloToma Verde | Mar 13 | May 1 | Jul 10 | 70 from transplant |
| Roma TomatoRoma VF (determinate paste) | Mar 13 | May 1 | Jul 15 | 75 from transplant |
| San Marzano TomatoSan Marzano (indeterminate paste) | Mar 13 | May 1 | Jul 20 | 80 from transplant |
Tight means first harvest lands within two weeks of the median first fall frost: start that crop indoors on time or cover it in fall.
What sauce can Rockford grow?
Each sauce, scheduled for a Rockford container garden: when the first seeds go in and when enough fruit has ripened for one batch.
Rockford frost questions
When is the last frost in Rockford, IL?
The median last 32 °F freeze at ROCKFORD GTR ROCKFORD AP, IL is April 24: half of years see a later one. One year in ten, a freeze still comes after May 8; nine years in ten, it comes after April 10. Source: NOAA NCEI 1991–2020 U.S. Climate Normals.
When is the first frost in Rockford, IL?
The median first 32 °F freeze of fall is October 17. One year in ten it arrives before October 2; nine years in ten, before October 30.
How long is the growing season in Rockford, IL?
174 days between the last spring and first fall 32 °F freeze in a median year. Nine years in ten the season runs at least 154 days; one year in ten, at least 192 days.
What growing zone is Rockford, IL?
USDA hardiness zone 5b, per the 2023 USDA Plant Hardiness Zone Map for ZIP 61104. A zone describes the coldest winter night, not when frost ends, so it is the wrong number for a planting calendar — the frost dates on this page are the right one.
When should I plant tomatoes in Rockford, IL?
Start Roma VF (determinate paste) seeds indoors around Mar 13 and transplant around May 1, 1 week after the median last frost. To cut the freeze risk to one year in ten, wait for May 8. First ripe fruit lands around Jul 15.
When should I plant peppers in Rockford, IL?
Sow jalapeño indoors on a heat mat around Feb 27; transplant no earlier than May 1, and wait past it until nights hold above 50 °F — that can run weeks later. First green pods around Jul 15.
Nearby in Illinois
- Crystal Lakelast frost May 1
- Elginlast frost Apr 26
- Hoffman Estateslast frost Apr 30
- Auroralast frost Apr 19
- Schaumburglast frost Apr 30
- Palatinelast frost Apr 25
All Illinois frost dates → · How frost-date math drives a sowing calendar →