When to plant in Sycamore, IL
USDA Zone 5bSycamore, Illinois frost dates, USDA zone, and a full-year planting calendar, drawn from the nearest NOAA station and tuned to the local season.
In zone 5b, Sycamore gardeners can grow many hardy perennials, while the last and first frost still dictate the annual vegetable calendar.
The average first fall frost in Sycamore is now 7 days later than in the 1981–2010 normals. See how frost dates are shifting nationwide →
Frost probability
DE KALB · 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 Sycamore’s own odds, recorded at DE KALB.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 22 | May 4 | Apr 20 | Sep 25 | Oct 7 | Oct 21 |
| 32°F | May 10 | Apr 24 | Apr 9 | Oct 4 | Oct 18 | Oct 31 |
| 28°F | Apr 29 | Apr 13 | Mar 30 | Oct 14 | Oct 28 | Nov 12 |
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 Sycamore, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 30 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.
Sycamore planting FAQ
When is the last spring frost in Sycamore, IL?
Plan for the last spring frost in Sycamore around April 24 (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 Sycamore, IL?
Expect Sycamore's first fall frost near October 18 — a 50% chance of 32°F by that date. Bring in or cover tender crops ahead of it.
What hardiness zone is Sycamore in?
Sycamore 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 Sycamore?
Sycamore has about 177 frost-free days — a moderate growing season — between the average last spring frost (April 24) and first fall frost (October 18).
When should I plant tomatoes in Sycamore?
For Sycamore, sow tomatoes indoors about February 27–March 13 and move the seedlings out around May 1, after the last spring frost.
Never miss a window in Sycamore
An email when it’s time to start seeds, transplant, and sow — timed to Sycamore’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- DeKalb · 10 km
- Campton Hills · 22 km
- Pingree Grove · 23 km
- Huntley · 27 km
- Elgin · 29 km
- South Elgin · 30 km
- Geneva · 31 km
- St. Charles · 32 km
Frost dates recorded at DE KALB, 11 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 Sycamore, IL — Frost Dates & Zone 5b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00112223. Retrieved from https://blissgarden.com/illinois/sycamore.