Frost dates for 61720Anchor, IL
The average last spring frost in Anchor is April 21 and the average first fall frost is October 17, giving a typical growing season of about 178 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 21
- Average first fall frost
- Oct 17
- Growing season
- 178 days
Safer after May 5 (1-in-10 risk)
Possible by Oct 5 (1-in-10 risk)
Last frost typically in 174 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 19 · Apr 30 · May 16 | Sep 24 · Oct 7 · Oct 20 | 158 days | 100% |
| Frost / freeze (32°F) | Apr 10 · Apr 21 · May 5 | Oct 5 · Oct 17 · Oct 29 | 178 days | 100% |
| Hard freeze (28°F) | Mar 30 · Apr 11 · Apr 24 | Oct 15 · Oct 28 · Nov 12 | 200 days | 100% |
Planting calendar for Anchor
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 21 – May 27 |
| Tomatoes | Transplant outdoors | May 7 – Jun 27 |
| Peppers | Start seeds indoors | Mar 21 – Apr 21 |
| Peppers | Transplant outdoors | May 21 – Jun 21 |
| Eggplant | Start seeds indoors | Apr 7 – May 6 |
| Eggplant | Transplant outdoors | May 21 – Jun 21 |
| Cucumbers | Sow outdoors | May 21 – Jul 7 |
| Summer squash | Sow outdoors | May 7 – Jun 21 |
| Winter squash & pumpkins | Sow outdoors | May 21 – Jun 21 |
| Snap beans | Sow outdoors | May 7 – Jul 30 |
| Sweet corn | Sow outdoors | May 7 – Jun 27 |
| Watermelon & cantaloupe | Sow outdoors | May 21 – Jun 21 |
| Okra | Sow outdoors | May 14 – Jun 6 |
| Peas | Sow outdoors (spring) | Mar 21 – May 6 |
| Potatoes | Plant outdoors (spring) | Mar 21 – May 21 |
| Onions | Start seeds indoors (spring) | Feb 7 – Mar 6 |
| Onions | Transplant outdoors (spring) | Apr 7 – May 6 |
| Broccoli | Start seeds indoors (spring) | Mar 3 – Apr 6 |
| Broccoli | Transplant outdoors (spring) | Apr 7 – May 6 |
| Broccoli | Start seeds indoors (fall) | Jun 17 – Jun 27 |
| Broccoli | Transplant outdoors (fall) | Jul 17 – Jul 28 |
| Cabbage | Start seeds indoors (spring) | Feb 21 – Mar 21 |
| Cabbage | Transplant outdoors (spring) | Mar 21 – Apr 21 |
| Cabbage | Start seeds indoors (fall) | Jun 7 – Jul 7 |
| Cabbage | Transplant outdoors (fall) | Jul 7 – Aug 7 |
| Leaf lettuce | Sow outdoors (spring) | Mar 21 – Jun 6 |
| Leaf lettuce | Sow outdoors (fall) | Jul 7 – Aug 23 |
| Spinach | Sow outdoors (spring) | Mar 14 – Apr 27 |
| Spinach | Sow outdoors (fall) | Jul 24 – Aug 28 |
| Radishes | Sow outdoors (spring) | Mar 21 – May 11 |
| Radishes | Sow outdoors (fall) | Jul 7 – Sep 7 |
| Kale | Sow outdoors (spring) | Apr 7 – Apr 27 |
| Kale | Sow outdoors (fall) | Jun 30 – Aug 7 |
| Carrots | Sow outdoors (spring) | Apr 21 – Jun 6 |
| Carrots | Sow outdoors (fall) | Jun 7 – Jul 23 |
| Garlic | Plant outdoors (fall) | Oct 7 – Nov 7 |
Where these dates come from
ZIP code 61720 is matched to the NOAA station Gibson City, IL, 15.8 km away, at 750 ft elevation (21 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Gibson City, IL (used) | 750 ft | Apr 21 | Oct 17 |
| Chenoa, IL | 719 ft | Apr 23 | Oct 15 |
| Paxton 2 Wsw, IL | 758 ft | Apr 23 | Oct 12 |
| Normal 4Ne, IL | 790 ft | Apr 25 | Oct 16 |
Frost dates near Anchor
- Cropsey, IL 61731 · last Apr 21, first Oct 17
- Colfax, IL 61728 · last Apr 23, first Oct 15
- Saybrook, IL 61770 · last Apr 21, first Oct 17
- Sibley, IL 61773 · last Apr 21, first Oct 17
- Strawn, IL 61775 · last Apr 21, first Oct 17
- Gibson City, IL 60936 · last Apr 21, first Oct 17
- Arrowsmith, IL 61722 · last Apr 21, first Oct 17
- Cooksville, IL 61730 · last Apr 25, first Oct 16
Frequently asked questions
- When is the last frost in Anchor, IL?
- For ZIP code 61720, the average last spring frost (32°F) is April 21, based on NOAA 1991-2020 climate normals for the Gibson City, IL weather station. There is a 1-in-10 chance of a frost after May 5.
- When is the first frost in Anchor, IL?
- The average first fall frost (32°F) is October 17. There is a 1-in-10 chance of frost by October 5, so tender plants are at risk from that point on.
- How long is the growing season in 61720?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 178 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.