Frost dates for 52642Rome, IA
The average last spring frost in Rome is April 30 and the average first fall frost is October 10, giving a typical growing season of about 163 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 30
- Average first fall frost
- Oct 10
- Growing season
- 163 days
Safer after May 14 (1-in-10 risk)
Possible by Sep 24 (1-in-10 risk)
Last frost typically in 181 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 25 · May 9 · May 23 | Sep 16 · Oct 1 · Oct 13 | 144 days | 100% |
| Frost / freeze (32°F) | Apr 13 · Apr 30 · May 14 | Sep 24 · Oct 10 · Oct 23 | 163 days | 100% |
| Hard freeze (28°F) | Apr 3 · Apr 17 · May 5 | Oct 3 · Oct 20 · Nov 2 | 185 days | 100% |
Planting calendar for Rome
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 30 – Jun 5 |
| Tomatoes | Transplant outdoors | May 16 – Jun 20 |
| Peppers | Start seeds indoors | Mar 30 – Apr 30 |
| Peppers | Transplant outdoors | May 30 – Jun 30 |
| Eggplant | Start seeds indoors | Apr 16 – May 15 |
| Eggplant | Transplant outdoors | May 30 – Jun 30 |
| Cucumbers | Sow outdoors | May 30 – Jun 30 |
| Summer squash | Sow outdoors | May 16 – Jun 30 |
| Winter squash & pumpkins | Sow outdoors | May 30 – Jun 30 |
| Snap beans | Sow outdoors | May 16 – Jul 23 |
| Sweet corn | Sow outdoors | May 16 – Jun 20 |
| Watermelon & cantaloupe | Sow outdoors | May 30 – Jun 30 |
| Okra | Sow outdoors | May 23 – Jun 15 |
| Peas | Sow outdoors (spring) | Mar 30 – May 15 |
| Potatoes | Plant outdoors (spring) | Mar 30 – May 30 |
| Onions | Start seeds indoors (spring) | Feb 16 – Mar 15 |
| Onions | Transplant outdoors (spring) | Apr 16 – May 15 |
| Broccoli | Start seeds indoors (spring) | Mar 12 – Apr 15 |
| Broccoli | Transplant outdoors (spring) | Apr 16 – May 15 |
| Broccoli | Start seeds indoors (fall) | Jun 10 – Jun 20 |
| Broccoli | Transplant outdoors (fall) | Jul 10 – Jul 21 |
| Cabbage | Start seeds indoors (spring) | Mar 2 – Mar 30 |
| Cabbage | Transplant outdoors (spring) | Mar 30 – Apr 30 |
| Cabbage | Start seeds indoors (fall) | May 31 – Jun 30 |
| Cabbage | Transplant outdoors (fall) | Jun 30 – Jul 31 |
| Leaf lettuce | Sow outdoors (spring) | Mar 30 – Jun 15 |
| Leaf lettuce | Sow outdoors (fall) | Jun 30 – Aug 16 |
| Spinach | Sow outdoors (spring) | Mar 23 – May 6 |
| Spinach | Sow outdoors (fall) | Jul 17 – Aug 21 |
| Radishes | Sow outdoors (spring) | Mar 30 – May 20 |
| Radishes | Sow outdoors (fall) | Jun 30 – Aug 31 |
| Kale | Sow outdoors (spring) | Apr 16 – May 6 |
| Kale | Sow outdoors (fall) | Jun 23 – Jul 31 |
| Carrots | Sow outdoors (spring) | Apr 30 – Jun 15 |
| Carrots | Sow outdoors (fall) | May 31 – Jul 16 |
| Garlic | Plant outdoors (fall) | Sep 30 – Oct 31 |
Where these dates come from
ZIP code 52642 is matched to the NOAA station Mt Pleasant 1 Ssw, IA, 11.2 km away, at 730 ft elevation (90 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Mt Pleasant 1 Ssw, IA (used) | 730 ft | Apr 30 | Oct 10 |
| Fairfield, IA | 740 ft | Apr 27 | Oct 12 |
| Washington, IA | 687 ft | Apr 28 | Oct 11 |
| Keosauqua, IA | 629 ft | Apr 26 | Oct 13 |
Frost dates near Rome
- Lockridge, IA 52635 · last Apr 27, first Oct 12
- Mount Pleasant, IA 52641 · last Apr 30, first Oct 10
- Salem, IA 52649 · last Apr 30, first Oct 10
- Hillsboro, IA 52630 · last Apr 30, first Oct 10
- Stockport, IA 52651 · last Apr 27, first Oct 12
- Swedesburg, IA 52652 · last Apr 30, first Oct 10
- Wayland, IA 52654 · last Apr 28, first Oct 11
- Olds, IA 52647 · last Apr 30, first Oct 10
Frequently asked questions
- When is the last frost in Rome, IA?
- For ZIP code 52642, the average last spring frost (32°F) is April 30, based on NOAA 1991-2020 climate normals for the Mt Pleasant 1 Ssw, IA weather station. There is a 1-in-10 chance of a frost after May 14.
- When is the first frost in Rome, IA?
- The average first fall frost (32°F) is October 10. There is a 1-in-10 chance of frost by September 24, so tender plants are at risk from that point on.
- How long is the growing season in 52642?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 163 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.