Frost dates for 50840Clearfield, IA
The average last spring frost in Clearfield is April 24 and the average first fall frost is October 15, giving a typical growing season of about 173 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 24
- Average first fall frost
- Oct 15
- Growing season
- 173 days
Safer after May 6 (1-in-10 risk)
Possible by Oct 1 (1-in-10 risk)
Last frost typically in 179 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 20 · May 3 · May 16 | Sep 23 · Oct 5 · Oct 18 | 155 days | 100% |
| Frost / freeze (32°F) | Apr 9 · Apr 24 · May 6 | Oct 1 · Oct 15 · Oct 29 | 173 days | 100% |
| Hard freeze (28°F) | Mar 31 · Apr 14 · Apr 30 | Oct 11 · Oct 26 · Nov 6 | 192 days | 100% |
Planting calendar for Clearfield
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 24 – May 30 |
| Tomatoes | Transplant outdoors | May 10 – Jun 25 |
| Peppers | Start seeds indoors | Mar 24 – Apr 24 |
| Peppers | Transplant outdoors | May 24 – Jun 24 |
| Eggplant | Start seeds indoors | Apr 10 – May 9 |
| Eggplant | Transplant outdoors | May 24 – Jun 24 |
| Cucumbers | Sow outdoors | May 24 – Jul 5 |
| Summer squash | Sow outdoors | May 10 – Jun 24 |
| Winter squash & pumpkins | Sow outdoors | May 24 – Jun 24 |
| Snap beans | Sow outdoors | May 10 – Jul 28 |
| Sweet corn | Sow outdoors | May 10 – Jun 25 |
| Watermelon & cantaloupe | Sow outdoors | May 24 – Jun 24 |
| Okra | Sow outdoors | May 17 – Jun 9 |
| Peas | Sow outdoors (spring) | Mar 24 – May 9 |
| Potatoes | Plant outdoors (spring) | Mar 24 – May 24 |
| Onions | Start seeds indoors (spring) | Feb 10 – Mar 9 |
| Onions | Transplant outdoors (spring) | Apr 10 – May 9 |
| Broccoli | Start seeds indoors (spring) | Mar 6 – Apr 9 |
| Broccoli | Transplant outdoors (spring) | Apr 10 – May 9 |
| Broccoli | Start seeds indoors (fall) | Jun 15 – Jun 25 |
| Broccoli | Transplant outdoors (fall) | Jul 15 – Jul 26 |
| Cabbage | Start seeds indoors (spring) | Feb 24 – Mar 24 |
| Cabbage | Transplant outdoors (spring) | Mar 24 – Apr 24 |
| Cabbage | Start seeds indoors (fall) | Jun 5 – Jul 5 |
| Cabbage | Transplant outdoors (fall) | Jul 5 – Aug 5 |
| Leaf lettuce | Sow outdoors (spring) | Mar 24 – Jun 9 |
| Leaf lettuce | Sow outdoors (fall) | Jul 5 – Aug 21 |
| Spinach | Sow outdoors (spring) | Mar 17 – Apr 30 |
| Spinach | Sow outdoors (fall) | Jul 22 – Aug 26 |
| Radishes | Sow outdoors (spring) | Mar 24 – May 14 |
| Radishes | Sow outdoors (fall) | Jul 5 – Sep 5 |
| Kale | Sow outdoors (spring) | Apr 10 – Apr 30 |
| Kale | Sow outdoors (fall) | Jun 28 – Aug 5 |
| Carrots | Sow outdoors (spring) | Apr 24 – Jun 9 |
| Carrots | Sow outdoors (fall) | Jun 5 – Jul 21 |
| Garlic | Plant outdoors (fall) | Oct 5 – Nov 5 |
Where these dates come from
ZIP code 50840 is matched to the NOAA station Bedford, IA, 23.5 km away, at 1,190 ft elevation (57 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Bedford, IA (used) | 1,190 ft | Apr 24 | Oct 15 |
| Mt Ayr, IA | 1,140 ft | Apr 25 | Oct 12 |
| Creston 2 Sw, IA | 1,296 ft | Apr 28 | Oct 11 |
| Corning, IA | 1,190 ft | Apr 27 | Oct 12 |
Frost dates near Clearfield
- Lenox, IA 50851 · last Apr 28, first Oct 11
- Diagonal, IA 50845 · last Apr 25, first Oct 12
- Sharpsburg, IA 50862 · last Apr 24, first Oct 15
- Benton, IA 50835 · last Apr 25, first Oct 12
- Blockton, IA 50836 · last Apr 24, first Oct 15
- Gravity, IA 50848 · last Apr 24, first Oct 15
- Shannon City, IA 50861 · last Apr 23, first Oct 17
- Mount Ayr, IA 50854 · last Apr 25, first Oct 12
Frequently asked questions
- When is the last frost in Clearfield, IA?
- For ZIP code 50840, the average last spring frost (32°F) is April 24, based on NOAA 1991-2020 climate normals for the Bedford, IA weather station. There is a 1-in-10 chance of a frost after May 6.
- When is the first frost in Clearfield, IA?
- The average first fall frost (32°F) is October 15. 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 50840?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 173 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.