When to plant in Chicago, IL
USDA Zone 6aChicago, Illinois frost dates, USDA zone, and a full-year planting calendar, drawn from the nearest NOAA station and tuned to the local season.
Zone 6a means Chicago sees real winter cold, but a good range of perennials survive; the frost dates above govern when annual vegetables go out.
Frost probability
CHICAGO NORTHERLY IS · 1991–2020The date the last spring and first fall frost occur, by threshold and probability. A 90% date is later in spring — and earlier in fall — than a 10% date; the 50% · 32°F row is what most gardeners plan around. These are Chicago’s own odds, recorded at CHICAGO NORTHERLY IS.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 9 | Apr 23 | Apr 9 | Oct 12 | Oct 26 | Nov 7 |
| 32°F | Apr 25 | Apr 10 | Mar 29 | Oct 24 | Nov 5 | Nov 20 |
| 28°F | Apr 14 | Apr 1 | Mar 16 | Nov 2 | Nov 15 | Dec 1 |
Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.
What to plant now
TODAY · JULY 19Full-year planting calendar
Each bar is the exact window to take a planting action in Chicago, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 13 km · complete 32°F normalsWhen stations disagree by more than a few days, that spread is real microclimate variation — elevation, water, urban heat. Judge which station best matches your own yard.
Chicago planting FAQ
When is the last spring frost in Chicago, IL?
On average, the last spring frost in Chicago is around April 10 (50% probability at 32°F, from 1991–2020 NOAA normals). Wait until after this date to set out tender plants like tomatoes and peppers.
When is the first fall frost in Chicago, IL?
In Chicago, the first 32°F freeze of fall lands around November 5 on average. Time your last harvests and any season-extension cover before it.
What hardiness zone is Chicago in?
Chicago is in USDA hardiness zone 6a. In zone 6a, winters are moderate — most common vegetables grow well in season.
How long is the growing season in Chicago?
There are roughly 209 frost-free days in Chicago (a moderate growing season), running from the average last frost around April 10 to the first fall frost near November 5.
When should I plant tomatoes in Chicago?
In Chicago, start tomato seeds indoors around February 13–February 27, then transplant seedlings outdoors around April 17 once the danger of frost has passed.
Never miss a window in Chicago
An email when it’s time to start seeds, transplant, and sow — timed to Chicago’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Cicero · 6 km
- Berwyn · 9 km
- Oak Park · 10 km
- Forest Park · 11 km
- Lyons · 11 km
- Summit · 12 km
- Burbank · 12 km
- River Forest · 13 km
Frost dates recorded at CHICAGO NORTHERLY IS, 7 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.
BlissGarden. "When to Plant in Chicago, IL — Frost Dates & Zone 6a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00111550. Retrieved from https://blissgarden.com/illinois/chicago.