Frost dates for 51652Sidney, IA
The average last spring frost in Sidney is April 19 and the average first fall frost is October 19, giving a typical growing season of about 182 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 19
- Average first fall frost
- Oct 19
- Growing season
- 182 days
Safer after May 2 (1-in-10 risk)
Possible by Oct 1 (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 15 · Apr 30 · May 11 | Sep 23 · Oct 9 · Oct 22 | 162 days | 100% |
| Frost / freeze (32°F) | Apr 5 · Apr 19 · May 2 | Oct 1 · Oct 19 · Oct 31 | 182 days | 100% |
| Hard freeze (28°F) | Mar 25 · Apr 9 · Apr 23 | Oct 16 · Oct 29 · Nov 12 | 203 days | 100% |
Planting calendar for Sidney
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 19 – May 25 |
| Tomatoes | Transplant outdoors | May 5 – Jun 29 |
| Peppers | Start seeds indoors | Mar 19 – Apr 19 |
| Peppers | Transplant outdoors | May 19 – Jun 19 |
| Eggplant | Start seeds indoors | Apr 5 – May 4 |
| Eggplant | Transplant outdoors | May 19 – Jun 19 |
| Cucumbers | Sow outdoors | May 19 – Jul 9 |
| Summer squash | Sow outdoors | May 5 – Jun 19 |
| Winter squash & pumpkins | Sow outdoors | May 19 – Jun 19 |
| Snap beans | Sow outdoors | May 5 – Aug 1 |
| Sweet corn | Sow outdoors | May 5 – Jun 29 |
| Watermelon & cantaloupe | Sow outdoors | May 19 – Jun 19 |
| Okra | Sow outdoors | May 12 – Jun 4 |
| Peas | Sow outdoors (spring) | Mar 19 – May 4 |
| Potatoes | Plant outdoors (spring) | Mar 19 – May 19 |
| Onions | Start seeds indoors (spring) | Feb 5 – Mar 4 |
| Onions | Transplant outdoors (spring) | Apr 5 – May 4 |
| Broccoli | Start seeds indoors (spring) | Mar 1 – Apr 4 |
| Broccoli | Transplant outdoors (spring) | Apr 5 – May 4 |
| Broccoli | Start seeds indoors (fall) | Jun 19 – Jun 29 |
| Broccoli | Transplant outdoors (fall) | Jul 19 – Jul 30 |
| Cabbage | Start seeds indoors (spring) | Feb 19 – Mar 19 |
| Cabbage | Transplant outdoors (spring) | Mar 19 – Apr 19 |
| Cabbage | Start seeds indoors (fall) | Jun 9 – Jul 9 |
| Cabbage | Transplant outdoors (fall) | Jul 9 – Aug 9 |
| Leaf lettuce | Sow outdoors (spring) | Mar 19 – Jun 4 |
| Leaf lettuce | Sow outdoors (fall) | Jul 9 – Aug 25 |
| Spinach | Sow outdoors (spring) | Mar 12 – Apr 25 |
| Spinach | Sow outdoors (fall) | Jul 26 – Aug 30 |
| Radishes | Sow outdoors (spring) | Mar 19 – May 9 |
| Radishes | Sow outdoors (fall) | Jul 9 – Sep 9 |
| Kale | Sow outdoors (spring) | Apr 5 – Apr 25 |
| Kale | Sow outdoors (fall) | Jul 2 – Aug 9 |
| Carrots | Sow outdoors (spring) | Apr 19 – Jun 4 |
| Carrots | Sow outdoors (fall) | Jun 9 – Jul 25 |
| Garlic | Plant outdoors (fall) | Oct 9 – Nov 9 |
Where these dates come from
ZIP code 51652 is matched to the NOAA station Sidney 1Sse, IA, 1.6 km away, at 1,140 ft elevation (71 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Sidney 1Sse, IA (used) | 1,140 ft | Apr 19 | Oct 19 |
| Nebraska City 2Nw, NE | 1,055 ft | Apr 18 | Oct 19 |
| Shenandoah, IA | 999 ft | Apr 20 | Oct 17 |
| Glenwood 3Sw, IA | 980 ft | Apr 23 | Oct 11 |
Frost dates near Sidney
- Riverton, IA 51650 · last Apr 19, first Oct 19
- Farragut, IA 51639 · last Apr 20, first Oct 17
- Percival, IA 51648 · last Apr 18, first Oct 19
- Thurman, IA 51654 · last Apr 19, first Oct 19
- Randolph, IA 51649 · last Apr 20, first Oct 17
- Hamburg, IA 51640 · last Apr 19, first Oct 19
- Tabor, IA 51653 · last Apr 19, first Oct 19
- Nebraska City, NE 68410 · last Apr 18, first Oct 19
Frequently asked questions
- When is the last frost in Sidney, IA?
- For ZIP code 51652, the average last spring frost (32°F) is April 19, based on NOAA 1991-2020 climate normals for the Sidney 1Sse, IA weather station. There is a 1-in-10 chance of a frost after May 2.
- When is the first frost in Sidney, IA?
- The average first fall frost (32°F) is October 19. There is a 1-in-10 chance of frost by October 1, so tender plants are at risk from that point on.
- How long is the growing season in 51652?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 182 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.