Frost dates for 61341Marseilles, IL
The average last spring frost in Marseilles is April 27 and the average first fall frost is October 17, giving a typical growing season of about 171 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 27
- Average first fall frost
- Oct 17
- Growing season
- 171 days
Safer after May 13 (1-in-10 risk)
Possible by Oct 3 (1-in-10 risk)
Last frost typically in 178 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 22 · May 7 · May 22 | Sep 24 · Oct 7 · Oct 20 | 152 days | 100% |
| Frost / freeze (32°F) | Apr 12 · Apr 27 · May 13 | Oct 3 · Oct 17 · Oct 29 | 171 days | 100% |
| Hard freeze (28°F) | Apr 2 · Apr 15 · May 1 | Oct 14 · Oct 27 · Nov 9 | 194 days | 100% |
Planting calendar for Marseilles
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 27 – Jun 2 |
| Tomatoes | Transplant outdoors | May 13 – Jun 27 |
| Peppers | Start seeds indoors | Mar 27 – Apr 27 |
| Peppers | Transplant outdoors | May 27 – Jun 27 |
| Eggplant | Start seeds indoors | Apr 13 – May 12 |
| Eggplant | Transplant outdoors | May 27 – Jun 27 |
| Cucumbers | Sow outdoors | May 27 – Jul 7 |
| Summer squash | Sow outdoors | May 13 – Jun 27 |
| Winter squash & pumpkins | Sow outdoors | May 27 – Jun 27 |
| Snap beans | Sow outdoors | May 13 – Jul 30 |
| Sweet corn | Sow outdoors | May 13 – Jun 27 |
| Watermelon & cantaloupe | Sow outdoors | May 27 – Jun 27 |
| Okra | Sow outdoors | May 20 – Jun 12 |
| Peas | Sow outdoors (spring) | Mar 27 – May 12 |
| Potatoes | Plant outdoors (spring) | Mar 27 – May 27 |
| Onions | Start seeds indoors (spring) | Feb 13 – Mar 12 |
| Onions | Transplant outdoors (spring) | Apr 13 – May 12 |
| Broccoli | Start seeds indoors (spring) | Mar 9 – Apr 12 |
| Broccoli | Transplant outdoors (spring) | Apr 13 – May 12 |
| Broccoli | Start seeds indoors (fall) | Jun 17 – Jun 27 |
| Broccoli | Transplant outdoors (fall) | Jul 17 – Jul 28 |
| Cabbage | Start seeds indoors (spring) | Feb 27 – Mar 27 |
| Cabbage | Transplant outdoors (spring) | Mar 27 – Apr 27 |
| Cabbage | Start seeds indoors (fall) | Jun 7 – Jul 7 |
| Cabbage | Transplant outdoors (fall) | Jul 7 – Aug 7 |
| Leaf lettuce | Sow outdoors (spring) | Mar 27 – Jun 12 |
| Leaf lettuce | Sow outdoors (fall) | Jul 7 – Aug 23 |
| Spinach | Sow outdoors (spring) | Mar 20 – May 3 |
| Spinach | Sow outdoors (fall) | Jul 24 – Aug 28 |
| Radishes | Sow outdoors (spring) | Mar 27 – May 17 |
| Radishes | Sow outdoors (fall) | Jul 7 – Sep 7 |
| Kale | Sow outdoors (spring) | Apr 13 – May 3 |
| Kale | Sow outdoors (fall) | Jun 30 – Aug 7 |
| Carrots | Sow outdoors (spring) | Apr 27 – Jun 12 |
| Carrots | Sow outdoors (fall) | Jun 7 – Jul 23 |
| Garlic | Plant outdoors (fall) | Oct 7 – Nov 7 |
Where these dates come from
ZIP code 61341 is matched to the NOAA station Marseilles Lock, IL, 4.9 km away, at 490 ft elevation (97 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Marseilles Lock, IL (used) | 490 ft | Apr 27 | Oct 17 |
| Ottawa 5Sw, IL | 525 ft | Apr 20 | Oct 22 |
| Morris 1 Nw, IL | 524 ft | Apr 20 | Oct 23 |
| Streator 3 Se, IL | 610 ft | Apr 12 | Oct 28 |
Frost dates near Marseilles
- Seneca, IL 61360 · last Apr 27, first Oct 17
- Ottawa, IL 61350 · last Apr 27, first Oct 17
- Wedron, IL 60557 · last Apr 27, first Oct 17
- Grand Ridge, IL 61325 · last Apr 20, first Oct 22
- Verona, IL 60479 · last Apr 27, first Oct 15
- Serena, IL 60549 · last Apr 27, first Oct 17
- Ransom, IL 60470 · last Apr 27, first Oct 15
- Sheridan, IL 60551 · last Apr 27, first Oct 17
Frequently asked questions
- When is the last frost in Marseilles, IL?
- For ZIP code 61341, the average last spring frost (32°F) is April 27, based on NOAA 1991-2020 climate normals for the Marseilles Lock, IL weather station. There is a 1-in-10 chance of a frost after May 13.
- When is the first frost in Marseilles, IL?
- The average first fall frost (32°F) is October 17. There is a 1-in-10 chance of frost by October 3, so tender plants are at risk from that point on.
- How long is the growing season in 61341?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 171 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.