Frost dates for 50609Beaman, IA
The average last spring frost in Beaman is April 29 and the average first fall frost is October 9, giving a typical growing season of about 160 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 29
- Average first fall frost
- Oct 9
- Growing season
- 160 days
Safer after May 12 (1-in-10 risk)
Possible by Sep 25 (1-in-10 risk)
Last frost typically in 184 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 7 · May 21 | Sep 16 · Sep 30 · Oct 11 | 144 days | 100% |
| Frost / freeze (32°F) | Apr 15 · Apr 29 · May 12 | Sep 25 · Oct 9 · Oct 20 | 160 days | 100% |
| Hard freeze (28°F) | Apr 4 · Apr 19 · May 3 | Oct 5 · Oct 18 · Oct 30 | 180 days | 100% |
Planting calendar for Beaman
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 29 – Jun 4 |
| Tomatoes | Transplant outdoors | May 15 – Jun 19 |
| Peppers | Start seeds indoors | Mar 29 – Apr 29 |
| Peppers | Transplant outdoors | May 29 – Jun 29 |
| Eggplant | Start seeds indoors | Apr 15 – May 14 |
| Eggplant | Transplant outdoors | May 29 – Jun 29 |
| Cucumbers | Sow outdoors | May 29 – Jun 29 |
| Summer squash | Sow outdoors | May 15 – Jun 29 |
| Winter squash & pumpkins | Sow outdoors | May 29 – Jun 29 |
| Snap beans | Sow outdoors | May 15 – Jul 22 |
| Sweet corn | Sow outdoors | May 15 – Jun 19 |
| Watermelon & cantaloupe | Sow outdoors | May 29 – Jun 29 |
| Okra | Sow outdoors | May 22 – Jun 14 |
| Peas | Sow outdoors (spring) | Mar 29 – May 14 |
| Potatoes | Plant outdoors (spring) | Mar 29 – May 29 |
| Onions | Start seeds indoors (spring) | Feb 15 – Mar 14 |
| Onions | Transplant outdoors (spring) | Apr 15 – May 14 |
| Broccoli | Start seeds indoors (spring) | Mar 11 – Apr 14 |
| Broccoli | Transplant outdoors (spring) | Apr 15 – May 14 |
| Broccoli | Start seeds indoors (fall) | Jun 9 – Jun 19 |
| Broccoli | Transplant outdoors (fall) | Jul 9 – Jul 20 |
| Cabbage | Start seeds indoors (spring) | Mar 1 – Mar 29 |
| Cabbage | Transplant outdoors (spring) | Mar 29 – Apr 29 |
| Cabbage | Start seeds indoors (fall) | May 30 – Jun 29 |
| Cabbage | Transplant outdoors (fall) | Jun 29 – Jul 30 |
| Leaf lettuce | Sow outdoors (spring) | Mar 29 – Jun 14 |
| Leaf lettuce | Sow outdoors (fall) | Jun 29 – Aug 15 |
| Spinach | Sow outdoors (spring) | Mar 22 – May 5 |
| Spinach | Sow outdoors (fall) | Jul 16 – Aug 20 |
| Radishes | Sow outdoors (spring) | Mar 29 – May 19 |
| Radishes | Sow outdoors (fall) | Jun 29 – Aug 30 |
| Kale | Sow outdoors (spring) | Apr 15 – May 5 |
| Kale | Sow outdoors (fall) | Jun 22 – Jul 30 |
| Carrots | Sow outdoors (spring) | Apr 29 – Jun 14 |
| Carrots | Sow outdoors (fall) | May 30 – Jul 15 |
| Garlic | Plant outdoors (fall) | Sep 29 – Oct 30 |
Where these dates come from
ZIP code 50609 is matched to the NOAA station Grundy Ctr, IA, 15 km away, at 985 ft elevation (72 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Grundy Ctr, IA (used) | 985 ft | Apr 29 | Oct 9 |
| Marshalltown Muni Ap, IA | 974 ft | Apr 30 | Oct 6 |
| Marshalltown, IA | 870 ft | Apr 28 | Oct 7 |
| Eldora, IA | 1,073 ft | Apr 27 | Oct 10 |
Frost dates near Beaman
- Conrad, IA 50621 · last Apr 30, first Oct 6
- Lincoln, IA 50652 · last Apr 29, first Oct 9
- Gladbrook, IA 50635 · last Apr 30, first Oct 6
- Grundy Center, IA 50638 · last Apr 29, first Oct 9
- Liscomb, IA 50148 · last Apr 30, first Oct 6
- Morrison, IA 50657 · last Apr 29, first Oct 9
- Whitten, IA 50269 · last Apr 27, first Oct 10
- Holland, IA 50642 · last Apr 29, first Oct 9
Frequently asked questions
- When is the last frost in Beaman, IA?
- For ZIP code 50609, the average last spring frost (32°F) is April 29, based on NOAA 1991-2020 climate normals for the Grundy Ctr, IA weather station. There is a 1-in-10 chance of a frost after May 12.
- When is the first frost in Beaman, IA?
- The average first fall frost (32°F) is October 9. 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 50609?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 160 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.