Frost dates for 62997Willisville, IL
The average last spring frost in Willisville is April 12 and the average first fall frost is October 22, giving a typical growing season of about 191 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 12
- Average first fall frost
- Oct 22
- Growing season
- 191 days
Safer after Apr 29 (1-in-10 risk)
Possible by Oct 7 (1-in-10 risk)
Last frost typically in 164 days
Frost risk by date
NOAA reports frost dates as probabilities. The middle date is the average (a 50% chance). For spring, the 10% date is a safer planting date: frost after it happens in about 1 year in 10. Light frost (36°F) can damage tender plants; a hard freeze (28°F) kills most annuals.
| Temperature | Last spring: 90% / 50% / 10% chance | First fall: 10% / 50% / 90% chance | Growing season (50%) | Years with at least one |
|---|---|---|---|---|
| Light frost (36°F) | Apr 10 · Apr 24 · May 11 | Sep 27 · Oct 12 · Oct 23 | 166 days | 100% |
| Frost / freeze (32°F) | Mar 29 · Apr 12 · Apr 29 | Oct 7 · Oct 22 · Nov 2 | 191 days | 100% |
| Hard freeze (28°F) | Mar 16 · Apr 1 · Apr 16 | Oct 19 · Nov 1 · Nov 16 | 213 days | 100% |
Planting calendar for Willisville
Planting windows from the University of Maryland Extension calendar, shifted to your average frost dates. Use them as a starting point and adjust for seed packet instructions and local conditions.
| Crop | Task | Window |
|---|---|---|
| Tomatoes | Start seeds indoors | Mar 12 – May 18 |
| Tomatoes | Transplant outdoors | Apr 28 – Jul 2 |
| Peppers | Start seeds indoors | Mar 12 – Apr 12 |
| Peppers | Transplant outdoors | May 12 – Jun 12 |
| Eggplant | Start seeds indoors | Mar 29 – Apr 27 |
| Eggplant | Transplant outdoors | May 12 – Jun 12 |
| Cucumbers | Sow outdoors | May 12 – Jul 12 |
| Summer squash | Sow outdoors | Apr 28 – Jun 12 |
| Winter squash & pumpkins | Sow outdoors | May 12 – Jun 12 |
| Snap beans | Sow outdoors | Apr 28 – Aug 4 |
| Sweet corn | Sow outdoors | Apr 28 – Jul 2 |
| Watermelon & cantaloupe | Sow outdoors | May 12 – Jun 12 |
| Okra | Sow outdoors | May 5 – May 28 |
| Peas | Sow outdoors (spring) | Mar 12 – Apr 27 |
| Potatoes | Plant outdoors (spring) | Mar 12 – May 12 |
| Onions | Start seeds indoors (spring) | Jan 29 – Feb 25 |
| Onions | Transplant outdoors (spring) | Mar 29 – Apr 27 |
| Broccoli | Start seeds indoors (spring) | Feb 22 – Mar 28 |
| Broccoli | Transplant outdoors (spring) | Mar 29 – Apr 27 |
| Broccoli | Start seeds indoors (fall) | Jun 22 – Jul 2 |
| Broccoli | Transplant outdoors (fall) | Jul 22 – Aug 2 |
| Cabbage | Start seeds indoors (spring) | Feb 12 – Mar 12 |
| Cabbage | Transplant outdoors (spring) | Mar 12 – Apr 12 |
| Cabbage | Start seeds indoors (fall) | Jun 12 – Jul 12 |
| Cabbage | Transplant outdoors (fall) | Jul 12 – Aug 12 |
| Leaf lettuce | Sow outdoors (spring) | Mar 12 – May 28 |
| Leaf lettuce | Sow outdoors (fall) | Jul 12 – Aug 28 |
| Spinach | Sow outdoors (spring) | Mar 5 – Apr 18 |
| Spinach | Sow outdoors (fall) | Jul 29 – Sep 2 |
| Radishes | Sow outdoors (spring) | Mar 12 – May 2 |
| Radishes | Sow outdoors (fall) | Jul 12 – Sep 12 |
| Kale | Sow outdoors (spring) | Mar 29 – Apr 18 |
| Kale | Sow outdoors (fall) | Jul 5 – Aug 12 |
| Carrots | Sow outdoors (spring) | Apr 12 – May 28 |
| Carrots | Sow outdoors (fall) | Jun 12 – Jul 28 |
| Garlic | Plant outdoors (fall) | Oct 12 – Nov 12 |
Where these dates come from
ZIP code 62997 is matched to the NOAA station Sparta 1 W, IL, 18.4 km away, at 535 ft elevation (36 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Sparta 1 W, IL (used) | 535 ft | Apr 12 | Oct 22 |
| Kaskaskia Rvr Navigation Lock, IL | 380 ft | Apr 8 | Oct 30 |
| Du Quoin 4 Se, IL | 420 ft | Apr 6 | Oct 22 |
| Carbondale Southern Il Ap, IL | 406 ft | Apr 9 | Oct 22 |
Frost dates near Willisville
- Percy, IL 62272 · last Apr 12, first Oct 22
- Cutler, IL 62238 · last Apr 12, first Oct 22
- Campbell Hill, IL 62916 · last Apr 12, first Oct 22
- Steeleville, IL 62288 · last Apr 12, first Oct 22
- Ava, IL 62907 · last Apr 9, first Oct 22
- Rockwood, IL 62280 · last Apr 19, first Oct 20
- Sparta, IL 62286 · last Apr 12, first Oct 22
- Walsh, IL 62297 · last Apr 12, first Oct 22
Frequently asked questions
- When is the last frost in Willisville, IL?
- For ZIP code 62997, the average last spring frost (32°F) is April 12, based on NOAA 1991-2020 climate normals for the Sparta 1 W, IL weather station. There is a 1-in-10 chance of a frost after April 29.
- When is the first frost in Willisville, IL?
- The average first fall frost (32°F) is October 22. There is a 1-in-10 chance of frost by October 7, so tender plants are at risk from that point on.
- How long is the growing season in 62997?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 191 days long.
- Are these frost dates a forecast?
- No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.