When to plant in Quincy, IL
USDA Zone 6aEverything below — frost dates, hardiness zone, and what to plant when in Quincy, Illinois — is derived from the closest NOAA station with complete climate normals.
In zone 6a, Quincy gardeners can grow many hardy perennials, while the last and first frost still dictate the annual vegetable calendar.
Frost probability
QUINCY DAM 21 · 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 Quincy’s own odds, recorded at QUINCY DAM 21.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 4 | Apr 19 | Apr 5 | Oct 5 | Oct 20 | Oct 31 |
| 32°F | Apr 23 | Apr 8 | Mar 24 | Oct 17 | Oct 30 | Nov 10 |
| 28°F | Apr 14 | Mar 30 | Mar 12 | Oct 28 | Nov 8 | Nov 23 |
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 Quincy, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 23 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.
Quincy planting FAQ
When is the last spring frost in Quincy, IL?
On average, the last spring frost in Quincy is around April 8 (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 Quincy, IL?
Expect Quincy's first fall frost near October 30 — a 50% chance of 32°F by that date. Bring in or cover tender crops ahead of it.
What hardiness zone is Quincy in?
Quincy 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 Quincy?
Quincy has about 205 frost-free days — a moderate growing season — between the average last spring frost (April 8) and first fall frost (October 30).
When should I plant tomatoes in Quincy?
For Quincy, sow tomatoes indoors about February 11–February 25 and move the seedlings out around April 15, after the last spring frost.
Never miss a window in Quincy
An email when it’s time to start seeds, transplant, and sow — timed to Quincy’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Hannibal · 25 km
- Fort Madison · 77 km
- Macomb · 84 km
- Mexico · 96 km
- Burlington · 100 km
- Jacksonville · 101 km
- Kirksville · 106 km
- Moberly · 107 km
Frost dates recorded at QUINCY DAM 21, 5 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 Quincy, IL — Frost Dates & Zone 6a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00117077. Retrieved from https://blissgarden.com/illinois/quincy.