Frost dates for 62418Brownstown, IL
The average last spring frost in Brownstown is April 3 and the average first fall frost is October 24, giving a typical growing season of about 202 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 3
- Average first fall frost
- Oct 24
- Growing season
- 202 days
Safer after Apr 25 (1-in-10 risk)
Possible by Oct 9 (1-in-10 risk)
Last frost typically in 156 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 18 · May 9 | Sep 27 · Oct 13 · Oct 28 | 177 days | 100% |
| Frost / freeze (32°F) | Mar 19 · Apr 3 · Apr 25 | Oct 9 · Oct 24 · Nov 8 | 202 days | 100% |
| Hard freeze (28°F) | Mar 10 · Mar 27 · Apr 13 | Oct 21 · Nov 4 · Nov 25 | 224 days | 100% |
Planting calendar for Brownstown
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 4 |
| 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 14 |
| Summer squash | Sow outdoors | Apr 19 – Jun 3 |
| Winter squash & pumpkins | Sow outdoors | May 3 – Jun 3 |
| Snap beans | Sow outdoors | Apr 19 – Aug 6 |
| Sweet corn | Sow outdoors | Apr 19 – Jul 4 |
| 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) | Jun 24 – Jul 4 |
| Broccoli | Transplant outdoors (fall) | Jul 24 – Aug 4 |
| Cabbage | Start seeds indoors (spring) | Feb 3 – Mar 3 |
| Cabbage | Transplant outdoors (spring) | Mar 3 – Apr 3 |
| Cabbage | Start seeds indoors (fall) | Jun 14 – Jul 14 |
| Cabbage | Transplant outdoors (fall) | Jul 14 – Aug 14 |
| Leaf lettuce | Sow outdoors (spring) | Mar 3 – May 19 |
| Leaf lettuce | Sow outdoors (fall) | Jul 14 – Aug 30 |
| Spinach | Sow outdoors (spring) | Feb 24 – Apr 9 |
| Spinach | Sow outdoors (fall) | Jul 31 – Sep 4 |
| Radishes | Sow outdoors (spring) | Mar 3 – Apr 23 |
| Radishes | Sow outdoors (fall) | Jul 14 – Sep 14 |
| Kale | Sow outdoors (spring) | Mar 20 – Apr 9 |
| Kale | Sow outdoors (fall) | Jul 7 – Aug 14 |
| Carrots | Sow outdoors (spring) | Apr 3 – May 19 |
| Carrots | Sow outdoors (fall) | Jun 14 – Jul 30 |
| Garlic | Plant outdoors (fall) | Oct 14 – Nov 14 |
Where these dates come from
ZIP code 62418 is matched to the NOAA station Brownstown 4 Sw, IL, 3.9 km away, at 530 ft elevation (57 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Brownstown 4 Sw, IL (used) | 530 ft | Apr 3 | Oct 24 |
| Vandalia, IL | 490 ft | Apr 10 | Oct 24 |
| Ramsey, IL | 600 ft | Apr 15 | Oct 19 |
| Effingham 3Sw, IL | 625 ft | Apr 13 | Oct 24 |
Frost dates near Brownstown
- Saint Elmo, IL 62458 · last Apr 3, first Oct 24
- Vandalia, IL 62471 · last Apr 10, first Oct 24
- Saint Peter, IL 62880 · last Apr 3, first Oct 24
- Altamont, IL 62411 · last Apr 13, first Oct 24
- Shobonier, IL 62885 · last Apr 10, first Oct 24
- Hagarstown, IL 62247 · last Apr 10, first Oct 24
- Ramsey, IL 62080 · last Apr 15, first Oct 19
- Farina, IL 62838 · last Apr 3, first Oct 24
Frequently asked questions
- When is the last frost in Brownstown, IL?
- For ZIP code 62418, the average last spring frost (32°F) is April 3, based on NOAA 1991-2020 climate normals for the Brownstown 4 Sw, IL weather station. There is a 1-in-10 chance of a frost after April 25.
- When is the first frost in Brownstown, IL?
- The average first fall frost (32°F) is October 24. There is a 1-in-10 chance of frost by October 9, so tender plants are at risk from that point on.
- How long is the growing season in 62418?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 202 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.