Frost dates for 50235Rippey, IA
The average last spring frost in Rippey is April 25 and the average first fall frost is October 10, giving a typical growing season of about 166 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 25
- Average first fall frost
- Oct 10
- Growing season
- 166 days
Safer after May 8 (1-in-10 risk)
Possible by Sep 25 (1-in-10 risk)
Last frost typically in 180 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 22 · May 5 · May 17 | Sep 17 · Sep 30 · Oct 13 | 146 days | 100% |
| Frost / freeze (32°F) | Apr 12 · Apr 25 · May 8 | Sep 25 · Oct 10 · Oct 24 | 166 days | 100% |
| Hard freeze (28°F) | Apr 2 · Apr 16 · Apr 30 | Oct 5 · Oct 22 · Nov 3 | 187 days | 100% |
Planting calendar for Rippey
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 25 – May 31 |
| Tomatoes | Transplant outdoors | May 11 – Jun 20 |
| Peppers | Start seeds indoors | Mar 25 – Apr 25 |
| Peppers | Transplant outdoors | May 25 – Jun 25 |
| Eggplant | Start seeds indoors | Apr 11 – May 10 |
| Eggplant | Transplant outdoors | May 25 – Jun 25 |
| Cucumbers | Sow outdoors | May 25 – Jun 30 |
| Summer squash | Sow outdoors | May 11 – Jun 25 |
| Winter squash & pumpkins | Sow outdoors | May 25 – Jun 25 |
| Snap beans | Sow outdoors | May 11 – Jul 23 |
| Sweet corn | Sow outdoors | May 11 – Jun 20 |
| Watermelon & cantaloupe | Sow outdoors | May 25 – Jun 25 |
| Okra | Sow outdoors | May 18 – Jun 10 |
| Peas | Sow outdoors (spring) | Mar 25 – May 10 |
| Potatoes | Plant outdoors (spring) | Mar 25 – May 25 |
| Onions | Start seeds indoors (spring) | Feb 11 – Mar 10 |
| Onions | Transplant outdoors (spring) | Apr 11 – May 10 |
| Broccoli | Start seeds indoors (spring) | Mar 7 – Apr 10 |
| Broccoli | Transplant outdoors (spring) | Apr 11 – May 10 |
| Broccoli | Start seeds indoors (fall) | Jun 10 – Jun 20 |
| Broccoli | Transplant outdoors (fall) | Jul 10 – Jul 21 |
| Cabbage | Start seeds indoors (spring) | Feb 25 – Mar 25 |
| Cabbage | Transplant outdoors (spring) | Mar 25 – Apr 25 |
| Cabbage | Start seeds indoors (fall) | May 31 – Jun 30 |
| Cabbage | Transplant outdoors (fall) | Jun 30 – Jul 31 |
| Leaf lettuce | Sow outdoors (spring) | Mar 25 – Jun 10 |
| Leaf lettuce | Sow outdoors (fall) | Jun 30 – Aug 16 |
| Spinach | Sow outdoors (spring) | Mar 18 – May 1 |
| Spinach | Sow outdoors (fall) | Jul 17 – Aug 21 |
| Radishes | Sow outdoors (spring) | Mar 25 – May 15 |
| Radishes | Sow outdoors (fall) | Jun 30 – Aug 31 |
| Kale | Sow outdoors (spring) | Apr 11 – May 1 |
| Kale | Sow outdoors (fall) | Jun 23 – Jul 31 |
| Carrots | Sow outdoors (spring) | Apr 25 – Jun 10 |
| Carrots | Sow outdoors (fall) | May 31 – Jul 16 |
| Garlic | Plant outdoors (fall) | Sep 30 – Oct 31 |
Where these dates come from
ZIP code 50235 is matched to the NOAA station Perry, IA, 12.8 km away, at 950 ft elevation (136 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Perry, IA (used) | 950 ft | Apr 25 | Oct 10 |
| Jefferson, IA | 1,055 ft | Apr 26 | Oct 9 |
| Boone, IA | 1,035 ft | Apr 28 | Oct 12 |
| Guthrie Ctr, IA | 1,065 ft | May 2 | Oct 3 |
Frost dates near Rippey
- Dawson, IA 50066 · last Apr 25, first Oct 10
- Grand Junction, IA 50107 · last Apr 26, first Oct 9
- Jamaica, IA 50128 · last Apr 26, first Oct 9
- Perry, IA 50220 · last Apr 25, first Oct 10
- Beaver, IA 50031 · last Apr 28, first Oct 12
- Jefferson, IA 50129 · last Apr 26, first Oct 9
- Cooper, IA 50059 · last Apr 26, first Oct 9
- Yale, IA 50277 · last May 2, first Oct 3
Frequently asked questions
- When is the last frost in Rippey, IA?
- For ZIP code 50235, the average last spring frost (32°F) is April 25, based on NOAA 1991-2020 climate normals for the Perry, IA weather station. There is a 1-in-10 chance of a frost after May 8.
- When is the first frost in Rippey, IA?
- The average first fall frost (32°F) is October 10. There is a 1-in-10 chance of frost by September 25, so tender plants are at risk from that point on.
- How long is the growing season in 50235?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 166 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.