Frost dates for 52660Yarmouth, IA
The average last spring frost in Yarmouth 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 Yarmouth
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 52660 is matched to the NOAA station Mt Pleasant 1 Ssw, IA, 22.3 km away, at 730 ft elevation (18 ft lower 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 |
| Gladstone Dam 18, IL | 538 ft | Apr 8 | Oct 29 |
| Burlington Muni Ap, IA | 692 ft | Apr 15 | Oct 20 |
| Burlington 2S, IA | 690 ft | Apr 18 | Oct 20 |
Frost dates near Yarmouth
- Sperry, IA 52650 · last Apr 15, first Oct 20
- New London, IA 52645 · last Apr 30, first Oct 10
- Mount Union, IA 52644 · last Apr 30, first Oct 10
- Morning Sun, IA 52640 · last Apr 26, first Oct 10
- Danville, IA 52623 · last Apr 15, first Oct 20
- Mediapolis, IA 52637 · last Apr 8, first Oct 29
- Middletown, IA 52638 · last Apr 15, first Oct 20
- Winfield, IA 52659 · last Apr 30, first Oct 10
Frequently asked questions
- When is the last frost in Yarmouth, IA?
- For ZIP code 52660, 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 Yarmouth, 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 52660?
- 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.