Frost dates for 62908Belknap, IL
The average last spring frost in Belknap is April 3 and the average first fall frost is November 5, giving a typical growing season of about 216 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 3
- Average first fall frost
- Nov 5
- Growing season
- 216 days
Safer after Apr 21 (1-in-10 risk)
Possible by Oct 23 (1-in-10 risk)
First frost typically in 4 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) | Mar 31 · Apr 14 · May 2 | Oct 13 · Oct 25 · Nov 6 | 193 days | 100% |
| Frost / freeze (32°F) | Mar 17 · Apr 3 · Apr 21 | Oct 23 · Nov 5 · Nov 22 | 216 days | 100% |
| Hard freeze (28°F) | Mar 2 · Mar 22 · Apr 7 | Nov 3 · Nov 17 · Dec 4 | 239 days | 100% |
Planting calendar for Belknap
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 3 – May 9 |
| Tomatoes | Transplant outdoors | Apr 19 – Jul 16 |
| Peppers | Start seeds indoors | Mar 3 – Apr 3 |
| Peppers | Transplant outdoors | May 3 – Jun 3 |
| Eggplant | Start seeds indoors | Mar 20 – Apr 18 |
| Eggplant | Transplant outdoors | May 3 – Jun 3 |
| Cucumbers | Sow outdoors | May 3 – Jul 26 |
| Summer squash | Sow outdoors | Apr 19 – Jun 3 |
| Winter squash & pumpkins | Sow outdoors | May 3 – Jun 3 |
| Snap beans | Sow outdoors | Apr 19 – Aug 18 |
| Sweet corn | Sow outdoors | Apr 19 – Jul 16 |
| Watermelon & cantaloupe | Sow outdoors | May 3 – Jun 3 |
| Okra | Sow outdoors | Apr 26 – May 19 |
| Peas | Sow outdoors (spring) | Mar 3 – Apr 18 |
| Potatoes | Plant outdoors (spring) | Mar 3 – May 3 |
| Onions | Start seeds indoors (spring) | Jan 20 – Feb 16 |
| Onions | Transplant outdoors (spring) | Mar 20 – Apr 18 |
| Broccoli | Start seeds indoors (spring) | Feb 13 – Mar 19 |
| Broccoli | Transplant outdoors (spring) | Mar 20 – Apr 18 |
| Broccoli | Start seeds indoors (fall) | Jul 6 – Jul 16 |
| Broccoli | Transplant outdoors (fall) | Aug 5 – Aug 16 |
| Cabbage | Start seeds indoors (spring) | Feb 3 – Mar 3 |
| Cabbage | Transplant outdoors (spring) | Mar 3 – Apr 3 |
| Cabbage | Start seeds indoors (fall) | Jun 26 – Jul 26 |
| Cabbage | Transplant outdoors (fall) | Jul 26 – Aug 26 |
| Leaf lettuce | Sow outdoors (spring) | Mar 3 – May 19 |
| Leaf lettuce | Sow outdoors (fall) | Jul 26 – Sep 11 |
| Spinach | Sow outdoors (spring) | Feb 24 – Apr 9 |
| Spinach | Sow outdoors (fall) | Aug 12 – Sep 16 |
| Radishes | Sow outdoors (spring) | Mar 3 – Apr 23 |
| Radishes | Sow outdoors (fall) | Jul 26 – Sep 26 |
| Kale | Sow outdoors (spring) | Mar 20 – Apr 9 |
| Kale | Sow outdoors (fall) | Jul 19 – Aug 26 |
| Carrots | Sow outdoors (spring) | Apr 3 – May 19 |
| Carrots | Sow outdoors (fall) | Jun 26 – Aug 11 |
| Garlic | Plant outdoors (fall) | Oct 26 – Nov 26 |
Where these dates come from
ZIP code 62908 is matched to the NOAA station Grand Chain Dam 53, IL, 15.9 km away, at 385 ft elevation (38 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Grand Chain Dam 53, IL (used) | 385 ft | Apr 3 | Nov 5 |
| Dixon Springs Agric Ctr, IL | 527 ft | Apr 14 | Oct 21 |
| Anna 2 Nne, IL | 640 ft | Apr 8 | Oct 29 |
| W Paducah 2W, KY | 413 ft | Apr 3 | Oct 27 |
Frost dates near Belknap
- Karnak, IL 62956 · last Apr 3, first Nov 5
- Cypress, IL 62923 · last Apr 3, first Nov 5
- Grand Chain, IL 62941 · last Apr 3, first Nov 5
- Vienna, IL 62995 · last Apr 14, first Oct 21
- Perks, IL 62973 · last Apr 3, first Nov 5
- Boles, IL 62909 · last Apr 14, first Oct 21
- Buncombe, IL 62912 · last Apr 8, first Oct 29
- Joppa, IL 62953 · last Apr 5, first Oct 28
Frequently asked questions
- When is the last frost in Belknap, IL?
- For ZIP code 62908, the average last spring frost (32°F) is April 3, based on NOAA 1991-2020 climate normals for the Grand Chain Dam 53, IL weather station. There is a 1-in-10 chance of a frost after April 21.
- When is the first frost in Belknap, IL?
- The average first fall frost (32°F) is November 5. There is a 1-in-10 chance of frost by October 23, so tender plants are at risk from that point on.
- How long is the growing season in 62908?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 216 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.