When to plant in Machesney Park, IL
USDA Zone 5bMachesney Park, Illinois frost dates, USDA zone, and a full-year planting calendar, drawn from the nearest NOAA station and tuned to the local season.
Machesney Park's nearest full-normals station sits about 15 km out, so treat these as a close estimate — local microclimate can nudge your first and last frost. In zone 5b, Machesney Park gardeners can grow many hardy perennials, while the last and first frost still dictate the annual vegetable calendar.
The average last spring frost in Machesney Park is now 8 days later than in the 1981–2010 normals. See how frost dates are shifting nationwide →
Frost probability
BELOIT · 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 Machesney Park’s own odds, recorded at BELOIT.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 27 | May 11 | Apr 29 | Sep 21 | Oct 1 | Oct 14 |
| 32°F | May 16 | May 1 | Apr 17 | Sep 28 | Oct 12 | Oct 24 |
| 28°F | May 4 | Apr 20 | Apr 4 | Oct 9 | Oct 23 | Nov 4 |
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 Machesney Park, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 24 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.
Machesney Park planting FAQ
When is the last spring frost in Machesney Park, IL?
Plan for the last spring frost in Machesney Park around May 1 (the date it has a 50% chance of a 32°F freeze). Anything frost-sensitive should go out after it.
When is the first fall frost in Machesney Park, IL?
The first fall frost in Machesney Park typically arrives around October 12 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.
What hardiness zone is Machesney Park in?
Machesney Park is in USDA hardiness zone 5b. In zone 5b, winters are cold — pick cold-hardy varieties and protect tender crops.
How long is the growing season in Machesney Park?
Machesney Park has about 164 frost-free days — a moderate growing season — between the average last spring frost (May 1) and first fall frost (October 12).
When should I plant tomatoes in Machesney Park?
For Machesney Park, sow tomatoes indoors about March 6–March 20 and move the seedlings out around May 8, after the last spring frost.
Never miss a window in Machesney Park
An email when it’s time to start seeds, transplant, and sow — timed to Machesney Park’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Loves Park · 4 km
- Roscoe · 7 km
- Rockford · 12 km
- Belvidere · 16 km
- Beloit · 17 km
- Janesville · 35 km
- Woodstock · 49 km
- Sycamore · 50 km
Frost dates recorded at BELOIT, 15 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 Machesney Park, IL — Frost Dates & Zone 5b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00470696. Retrieved from https://blissgarden.com/illinois/machesney-park.