Frost dates for ZIP 50475 (Sheffield, IA)
Average last spring and first fall frost dates with 10%, 50% and 90% odds, from NOAA's 1991–2020 climate normals for the nearest weather station, Hampton, IA (9 miles away).
- Average last spring frostApr 2950% chance of a 32°F freeze after this date
- Average first fall frostOct 950% chance of a 32°F freeze by this date
- Growing season (frost-free)162 daysmedian, 32°F threshold
- USDA hardiness zone5a-20 to -15°F avg. coldest night
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This week in your yard
As of Oct 17, 2026, from your frost dates, zone and soil temperature. Lawn timing · Vegetables · Pruning · Plants
Soil temperature now
2-inch depth
No soil station with a fresh reading within 62 miles.
4-inch depth
No soil station with a fresh reading within 62 miles.
Fall: Texas A&M AgriLife times fall pre-emergent (for winter weeds such as annual bluegrass) to soil cooling to about 70°F for several days. The 50–55°F band is the spring trigger. Always read and follow the product label.
7-day forecast and frost risk
The latest National Weather Service 7-day forecast and any Frost Advisory or Freeze Warning for 50475 load here. You can also open the NWS forecast for this ZIP.
Pre-emergent
No soil reading near this ZIP. Typical extension timing for your region: spring mid-April to early May.
Fertilizer window
Lawn region: North (cool-season). Timing only; always follow the product label.
- Kentucky bluegrass (cool-season): Early fall: Around Labor Day (late August–September); Late fall: Late October–November, before the ground freezes; Late spring: Optional around Memorial Day. Avoid: Early-spring and midsummer feeding (pushes top growth, favors crabgrass).
Plant now
No vegetable planting windows are open this week.
Prune now
No frost-timed pruning windows are open this week.
Spring-flowering shrubs are pruned right after their flowers fade, not by date. See the pruning guide.
Last spring frost odds
| Chance of a 32°F freeze after this date | Date |
|---|---|
| 90% (early: most years still freeze after this) | Apr 15 |
| 50% (the "average" last frost) | Apr 29 |
| 10% (cautious: only 1 year in 10 freezes later) | May 10 |
Most gardeners plant frost-tender crops (tomatoes, peppers, basil) after the 50% date, and closer to the 10% date for less risk.
First fall frost odds
| Chance the first 32°F freeze has happened by this date | Date |
|---|---|
| 10% (early: 1 year in 10 freezes this soon) | Sep 26 |
| 50% (the "average" first frost) | Oct 9 |
| 90% (late: most years have frozen by now) | Oct 22 |
Light frost, freeze and hard freeze
| Threshold | Last spring (50%) | First fall (50%) |
|---|---|---|
| 36°F (light frost possible on clear, calm nights) | May 7 | Sep 30 |
| 32°F (freeze) | Apr 29 | Oct 9 |
| 28°F (hard freeze) | Apr 19 | Oct 20 |
n/a means NOAA did not publish a date at that threshold for this station (usually because it rarely gets that cold).
Vegetable planting calendar for 50475
Dates count from your average last spring frost (Apr 29) and first fall frost (Oct 9). Half of years have a frost after the spring date, so give tender crops (tomatoes, peppers, squash) some slack.
| Crop | Start indoors | Spring planting | Fall planting |
|---|---|---|---|
| Tomato | Mar 4–18 | May 6–20 (transplant) | – |
| Pepper (sweet and hot) | Feb 18–Mar 4 | May 13–27 (transplant) | – |
| Eggplant | Feb 18–Mar 4 | May 13–27 (transplant) | – |
| Tomatillo | Mar 4–18 | May 6–20 (transplant) | – |
| Lettuce | Mar 4–18 | Apr 8–29 (transplant) Apr 1–May 13 (sow outdoors) | Aug 14–Sep 4 (transplant) Jul 31–Aug 28 (sowing) |
| Spinach | – | Mar 18–Apr 8 (sow outdoors) | Aug 14–Sep 4 (sowing) |
| Kale | Mar 4–18 | Apr 1–15 (transplant) Apr 1–15 (sow outdoors) | Jul 17–Aug 14 (transplant) Jul 3–31 (sowing) |
| Collards | Mar 4–18 | Apr 1–29 (transplant) Apr 1–29 (sow outdoors) | Jul 17–Aug 14 (transplant) Jul 3–31 (sowing) |
| Broccoli | Feb 18–Mar 4 | Apr 1–15 (transplant) | Jul 3–31 (transplant) |
| Cabbage | Feb 18–Mar 4 | Apr 1–15 (transplant) | Jul 3–31 (transplant) |
| Cauliflower | Feb 18–Mar 4 | Apr 15–29 (transplant) | Jul 3–31 (transplant) |
| Brussels sprouts | Feb 4–18 | Apr 1–15 (transplant) | Jun 19–Jul 10 (transplant) |
| Kohlrabi | Mar 4–18 | Apr 1–15 (transplant) Apr 1–15 (sow outdoors) | Jul 31–Aug 14 (sowing) |
| Bok choy / Asian greens | – | Apr 1–15 (sow outdoors) | Aug 14–28 (sowing) |
| Arugula | – | Apr 1–29 (sow outdoors) | Aug 14–Sep 11 (sowing) |
| Mustard greens | – | Apr 1–22 (sow outdoors) | Aug 14–28 (sowing) |
| Swiss chard | Mar 18–Apr 1 | Apr 15–May 6 (transplant) Apr 15–May 13 (sow outdoors) | Jul 31–Aug 14 (sowing) |
| Beet | – | Apr 1–29 (sow outdoors) | Jul 31–Aug 14 (sowing) |
| Carrot | – | Apr 8–May 6 (sow outdoors) | Jul 17–31 (sowing) |
| Radish | – | Mar 25–May 6 (sow outdoors) | Aug 28–Sep 11 (sowing) |
| Turnip | – | Apr 1–22 (sow outdoors) | Jul 31–Aug 14 (sowing) |
| Parsnip | – | Apr 8–29 (sow outdoors) | – |
| Pea (garden, snap, snow) | – | Mar 4–Apr 1 (sow outdoors) | Jul 17–31 (sowing) |
| Onion (bulbing) | Feb 4–18 | Mar 18–Apr 1 (transplant) | – |
| Green onion / scallion | – | Mar 18–Apr 15 (sow outdoors) | Jul 31–Aug 14 (sowing) |
| Leek | Feb 4–18 | Apr 1–15 (transplant) | – |
| Garlic | – | – | Aug 28–Sep 25 (sowing) |
| Shallot | – | Mar 18–Apr 1 (transplant) | Aug 28–Sep 25 (sowing) |
| Potato | – | Apr 1–15 (transplant) | Jun 19–Jul 3 (transplant) |
| Sweet potato | – | May 20–Jun 3 (transplant) | – |
| Sweet corn | – | May 6–20 (sow outdoors) | – |
| Bean, bush (snap) | – | May 6–20 (sow outdoors) | – |
| Bean, pole | – | May 6–20 (sow outdoors) | – |
| Lima bean | – | May 13–27 (sow outdoors) | – |
| Southern pea (cowpea, black-eyed pea) | – | May 20–Jun 10 (sow outdoors) | – |
| Cucumber | Apr 1–8 | May 6–20 (transplant) May 6–20 (sow outdoors) | – |
| Summer squash / zucchini | Apr 1–8 | May 6–20 (transplant) May 6–20 (sow outdoors) | – |
| Winter squash | Apr 1–8 | May 6–20 (transplant) May 6–20 (sow outdoors) | – |
| Pumpkin | – | May 6–20 (sow outdoors) | – |
| Watermelon | Apr 1–8 | May 13–27 (transplant) May 13–27 (sow outdoors) | – |
| Cantaloupe / muskmelon | Apr 1–8 | May 13–27 (transplant) May 13–27 (sow outdoors) | – |
| Okra | Mar 18–Apr 1 | May 13–27 (transplant) May 13–27 (sow outdoors) | – |
| Celery | Feb 4–18 | May 6–13 (transplant) | – |
| Basil | Mar 18–Apr 1 | May 6–20 (transplant) May 6–20 (sow outdoors) | – |
| Cilantro | – | Apr 15–May 13 (sow outdoors) | Aug 14–28 (sowing) |
| Parsley | Feb 18–Mar 4 | Apr 15–29 (transplant) Apr 8–29 (sow outdoors) | – |
| Dill | – | Apr 29–May 13 (sow outdoors) | Aug 14–28 (sowing) |
| Sunflower | – | Apr 29–May 13 (sow outdoors) | – |
| Asparagus (crowns) | – | Apr 1–15 (transplant) | – |
| Rhubarb (crowns) | – | Apr 1–15 (transplant) | – |
| Strawberry (plants) | – | Apr 1–15 (transplant) | Jul 31–Aug 28 (transplant) |
Typical ranges from university extension planting calendars, adjusted to your frost dates. Probabilities, not guarantees. Fall windows that would overlap spring planting are left out, as are fall crops of frost-tender plants where the frost-free season is under 210 days.
Where these numbers come from
Station: Hampton, IA (NOAA GHCN-Daily ID USC00133584), elevation 1,105 ft, 8.8 miles from the ZIP's center point. NOAA completeness flag: S (standard, 24+ years).
Nearby stations
| Station | Distance | Last frost (50%) | First frost (50%) |
|---|---|---|---|
| Mason City, IA | 19 mi | Apr 29 | Oct 7 |
| Mason City Muni AP, IA | 20 mi | May 3 | Oct 1 |
| Allison, IA | 23 mi | Apr 27 | Oct 8 |
The average last-frost dates of these stations span 7 days, a rough guide to local variation. See data sources & methods.
Frost questions for 50475
When is the last frost in 50475?
The average (50% chance) last spring freeze of 32°F for ZIP 50475 is April 29. For a more cautious planting date, use May 10, when only 1 year in 10 still sees a later freeze.
When is the first frost in 50475?
The average first fall freeze is October 9. In 1 year in 10 it comes by September 26.
What hardiness zone is 50475?
ZIP 50475 is in USDA zone 5a (-20 to -15°F average coldest winter night), per the 2023 USDA Plant Hardiness Zone Map ZIP listing.
What is the soil temperature in 50475 right now?
This page shows the latest 2-inch and 4-inch soil temperature from the nearest public soil station (USDA SCAN, NOAA USCRN or TexMesonet), or a labeled estimate when no station is close, against the 50–55°F spring pre-emergent band.
Nearby ZIP codes
50427 Chapin 50469 Rockwell 50433 Dougherty 50477 Swaledale 50605 Aredale 50441 Hampton 50452 Latimer 50479 Thornton
Other ZIP codes in Franklin County
50041 50227 50420 50427 50431 50441 50452 50601 50605 50633 All Franklin County frost dates · Iowa frost dates
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