Frost dates for 50551Jolley, IA
The average last spring frost in Jolley is April 26 and the average first fall frost is October 10, giving a typical growing season of about 167 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 26
- Average first fall frost
- Oct 10
- Growing season
- 167 days
Safer after May 6 (1-in-10 risk)
Possible by Sep 27 (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 23 · May 4 · May 15 | Sep 18 · Oct 1 · Oct 13 | 148 days | 100% |
| Frost / freeze (32°F) | Apr 11 · Apr 26 · May 6 | Sep 27 · Oct 10 · Oct 24 | 167 days | 100% |
| Hard freeze (28°F) | Apr 2 · Apr 16 · Apr 29 | Oct 6 · Oct 21 · Nov 4 | 188 days | 100% |
Planting calendar for Jolley
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 26 – Jun 1 |
| Tomatoes | Transplant outdoors | May 12 – Jun 20 |
| Peppers | Start seeds indoors | Mar 26 – Apr 26 |
| Peppers | Transplant outdoors | May 26 – Jun 26 |
| Eggplant | Start seeds indoors | Apr 12 – May 11 |
| Eggplant | Transplant outdoors | May 26 – Jun 26 |
| Cucumbers | Sow outdoors | May 26 – Jun 30 |
| Summer squash | Sow outdoors | May 12 – Jun 26 |
| Winter squash & pumpkins | Sow outdoors | May 26 – Jun 26 |
| Snap beans | Sow outdoors | May 12 – Jul 23 |
| Sweet corn | Sow outdoors | May 12 – Jun 20 |
| Watermelon & cantaloupe | Sow outdoors | May 26 – Jun 26 |
| Okra | Sow outdoors | May 19 – Jun 11 |
| Peas | Sow outdoors (spring) | Mar 26 – May 11 |
| Potatoes | Plant outdoors (spring) | Mar 26 – May 26 |
| Onions | Start seeds indoors (spring) | Feb 12 – Mar 11 |
| Onions | Transplant outdoors (spring) | Apr 12 – May 11 |
| Broccoli | Start seeds indoors (spring) | Mar 8 – Apr 11 |
| Broccoli | Transplant outdoors (spring) | Apr 12 – May 11 |
| Broccoli | Start seeds indoors (fall) | Jun 10 – Jun 20 |
| Broccoli | Transplant outdoors (fall) | Jul 10 – Jul 21 |
| Cabbage | Start seeds indoors (spring) | Feb 26 – Mar 26 |
| Cabbage | Transplant outdoors (spring) | Mar 26 – Apr 26 |
| Cabbage | Start seeds indoors (fall) | May 31 – Jun 30 |
| Cabbage | Transplant outdoors (fall) | Jun 30 – Jul 31 |
| Leaf lettuce | Sow outdoors (spring) | Mar 26 – Jun 11 |
| Leaf lettuce | Sow outdoors (fall) | Jun 30 – Aug 16 |
| Spinach | Sow outdoors (spring) | Mar 19 – May 2 |
| Spinach | Sow outdoors (fall) | Jul 17 – Aug 21 |
| Radishes | Sow outdoors (spring) | Mar 26 – May 16 |
| Radishes | Sow outdoors (fall) | Jun 30 – Aug 31 |
| Kale | Sow outdoors (spring) | Apr 12 – May 2 |
| Kale | Sow outdoors (fall) | Jun 23 – Jul 31 |
| Carrots | Sow outdoors (spring) | Apr 26 – Jun 11 |
| Carrots | Sow outdoors (fall) | May 31 – Jul 16 |
| Garlic | Plant outdoors (fall) | Sep 30 – Oct 31 |
Where these dates come from
ZIP code 50551 is matched to the NOAA station Rockwell City, IA, 14.5 km away, at 1,214 ft elevation (7 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Rockwell City, IA (used) | 1,214 ft | Apr 26 | Oct 10 |
| Sac City, IA | 1,210 ft | Apr 30 | Oct 6 |
| Pocahontas, IA | 1,212 ft | Apr 26 | Oct 7 |
| Storm Lake, IA | 1,442 ft | Apr 25 | Oct 13 |
Frost dates near Jolley
- Pomeroy, IA 50575 · last Apr 26, first Oct 10
- Lytton, IA 50561 · last Apr 30, first Oct 6
- Fonda, IA 50540 · last Apr 26, first Oct 7
- Rockwell City, IA 50579 · last Apr 26, first Oct 10
- Manson, IA 50563 · last Apr 26, first Oct 10
- Sac City, IA 50583 · last Apr 30, first Oct 6
- Varina, IA 50593 · last Apr 26, first Oct 7
- Lake City, IA 51449 · last Apr 26, first Oct 10
Frequently asked questions
- When is the last frost in Jolley, IA?
- For ZIP code 50551, the average last spring frost (32°F) is April 26, based on NOAA 1991-2020 climate normals for the Rockwell City, IA weather station. There is a 1-in-10 chance of a frost after May 6.
- When is the first frost in Jolley, IA?
- The average first fall frost (32°F) is October 10. There is a 1-in-10 chance of frost by September 27, so tender plants are at risk from that point on.
- How long is the growing season in 50551?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 167 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.