Fall in zone 4bPhoto: Dietmar Rabich, CC BY-SA 4.0, via Wikimedia Commons
Frost dates for ZIP 55370 (Plato, MN)
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, Brownton Wwtp, MN (15 miles away).
- Average last spring frostApr 3050% chance of a 32°F freeze after this date
- Average first fall frostOct 450% chance of a 32°F freeze by this date
- Growing season (frost-free)156 daysmedian, 32°F threshold
- USDA hardiness zone4b-25 to -20°F avg. coldest night
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This week in your yard
As of Oct 18, 2026, from your frost dates, zone and soil temperature. Lawn timing · Vegetables · Pruning · Plants
Soil temperature now
2-inch depth
49°F Below 50°F
24-hour average · latest 50°F, as of Oct 18, 2:00 AM CDT
Estimate Not a measurement at this ZIP: distance-weighted average of Crescent Lake #1 (44 mi).
4-inch depth
50°F 50–55°F
24-hour average · latest 51°F, as of Oct 18, 2:00 AM CDT
Estimate Not a measurement at this ZIP: distance-weighted average of Crescent Lake #1 (44 mi).
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 55370 load here. You can also open the NWS forecast for this ZIP.
Pre-emergent
Soil is 50°F at 4 inches (estimated soil temperature, not a station reading). Fall pre-emergent window is mostly past. Next: spring, when soil reaches 50°F (typically 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 17 |
| 50% (the "average" last frost) | Apr 30 |
| 10% (cautious: only 1 year in 10 freezes later) | May 13 |
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 21 |
| 50% (the "average" first frost) | Oct 4 |
| 90% (late: most years have frozen by now) | Oct 18 |
Light frost, freeze and hard freeze
| Threshold | Last spring (50%) | First fall (50%) |
|---|---|---|
| 36°F (light frost possible on clear, calm nights) | May 10 | Sep 26 |
| 32°F (freeze) | Apr 30 | Oct 4 |
| 28°F (hard freeze) | Apr 20 | Oct 15 |
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 55370
Dates count from your average last spring frost (Apr 30) and first fall frost (Oct 4). 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 5–19 | May 7–21 (transplant) | – |
| Pepper (sweet and hot) | Feb 19–Mar 5 | May 14–28 (transplant) | – |
| Eggplant | Feb 19–Mar 5 | May 14–28 (transplant) | – |
| Tomatillo | Mar 5–19 | May 7–21 (transplant) | – |
| Lettuce | Mar 5–19 | Apr 9–30 (transplant) Apr 2–May 14 (sow outdoors) | Aug 9–30 (transplant) Jul 26–Aug 23 (sowing) |
| Spinach | – | Mar 19–Apr 9 (sow outdoors) | Aug 9–30 (sowing) |
| Kale | Mar 5–19 | Apr 2–16 (transplant) Apr 2–16 (sow outdoors) | Jul 12–Aug 9 (transplant) Jun 28–Jul 26 (sowing) |
| Collards | Mar 5–19 | Apr 2–30 (transplant) Apr 2–30 (sow outdoors) | Jul 12–Aug 9 (transplant) Jun 28–Jul 26 (sowing) |
| Broccoli | Feb 19–Mar 5 | Apr 2–16 (transplant) | Jun 28–Jul 26 (transplant) |
| Cabbage | Feb 19–Mar 5 | Apr 2–16 (transplant) | Jun 28–Jul 26 (transplant) |
| Cauliflower | Feb 19–Mar 5 | Apr 16–30 (transplant) | Jun 28–Jul 26 (transplant) |
| Brussels sprouts | Feb 5–19 | Apr 2–16 (transplant) | Jun 14–Jul 5 (transplant) |
| Kohlrabi | Mar 5–19 | Apr 2–16 (transplant) Apr 2–16 (sow outdoors) | Jul 26–Aug 9 (sowing) |
| Bok choy / Asian greens | – | Apr 2–16 (sow outdoors) | Aug 9–23 (sowing) |
| Arugula | – | Apr 2–30 (sow outdoors) | Aug 9–Sep 6 (sowing) |
| Mustard greens | – | Apr 2–23 (sow outdoors) | Aug 9–23 (sowing) |
| Swiss chard | Mar 19–Apr 2 | Apr 16–May 7 (transplant) Apr 16–May 14 (sow outdoors) | Jul 26–Aug 9 (sowing) |
| Beet | – | Apr 2–30 (sow outdoors) | Jul 26–Aug 9 (sowing) |
| Carrot | – | Apr 9–May 7 (sow outdoors) | Jul 12–26 (sowing) |
| Radish | – | Mar 26–May 7 (sow outdoors) | Aug 23–Sep 6 (sowing) |
| Turnip | – | Apr 2–23 (sow outdoors) | Jul 26–Aug 9 (sowing) |
| Parsnip | – | Apr 9–30 (sow outdoors) | – |
| Pea (garden, snap, snow) | – | Mar 5–Apr 2 (sow outdoors) | Jul 12–26 (sowing) |
| Onion (bulbing) | Feb 5–19 | Mar 19–Apr 2 (transplant) | – |
| Green onion / scallion | – | Mar 19–Apr 16 (sow outdoors) | Jul 26–Aug 9 (sowing) |
| Leek | Feb 5–19 | Apr 2–16 (transplant) | – |
| Garlic | – | – | Aug 23–Sep 20 (sowing) |
| Shallot | – | Mar 19–Apr 2 (transplant) | Aug 23–Sep 20 (sowing) |
| Potato | – | Apr 2–16 (transplant) | Jun 14–28 (transplant) |
| Sweet potato | – | May 21–Jun 4 (transplant) | – |
| Sweet corn | – | May 7–21 (sow outdoors) | – |
| Bean, bush (snap) | – | May 7–21 (sow outdoors) | – |
| Bean, pole | – | May 7–21 (sow outdoors) | – |
| Lima bean | – | May 14–28 (sow outdoors) | – |
| Southern pea (cowpea, black-eyed pea) | – | May 21–Jun 11 (sow outdoors) | – |
| Cucumber | Apr 2–9 | May 7–21 (transplant) May 7–21 (sow outdoors) | – |
| Summer squash / zucchini | Apr 2–9 | May 7–21 (transplant) May 7–21 (sow outdoors) | – |
| Winter squash | Apr 2–9 | May 7–21 (transplant) May 7–21 (sow outdoors) | – |
| Pumpkin | – | May 7–21 (sow outdoors) | – |
| Watermelon | Apr 2–9 | May 14–28 (transplant) May 14–28 (sow outdoors) | – |
| Cantaloupe / muskmelon | Apr 2–9 | May 14–28 (transplant) May 14–28 (sow outdoors) | – |
| Okra | Mar 19–Apr 2 | May 14–28 (transplant) May 14–28 (sow outdoors) | – |
| Celery | Feb 5–19 | May 7–14 (transplant) | – |
| Basil | Mar 19–Apr 2 | May 7–21 (transplant) May 7–21 (sow outdoors) | – |
| Cilantro | – | Apr 16–May 14 (sow outdoors) | Aug 9–23 (sowing) |
| Parsley | Feb 19–Mar 5 | Apr 16–30 (transplant) Apr 9–30 (sow outdoors) | – |
| Dill | – | Apr 30–May 14 (sow outdoors) | Aug 9–23 (sowing) |
| Sunflower | – | Apr 30–May 14 (sow outdoors) | – |
| Asparagus (crowns) | – | Apr 2–16 (transplant) | – |
| Rhubarb (crowns) | – | Apr 2–16 (transplant) | – |
| Strawberry (plants) | – | Apr 2–16 (transplant) | Jul 26–Aug 23 (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: Brownton Wwtp, MN (NOAA GHCN-Daily ID USC00211065), elevation 1,040 ft, 15.5 miles from the ZIP's center point. NOAA completeness flag: R (representative, 10+ years).
Nearby stations
| Station | Distance | Last frost (50%) | First frost (50%) |
|---|---|---|---|
| Gaylord, MN | 18 mi | Apr 24 | Oct 15 |
| Hutchinson 1 N, MN | 18 mi | Apr 28 | Oct 8 |
| Chaska 2NW, MN | 20 mi | May 5 | Oct 5 |
The average last-frost dates of these stations span 12 days, a rough guide to local variation. See data sources & methods.
Frost questions for 55370
When is the last frost in 55370?
The average (50% chance) last spring freeze of 32°F for ZIP 55370 is April 30. For a more cautious planting date, use May 13, when only 1 year in 10 still sees a later freeze.
When is the first frost in 55370?
The average first fall freeze is October 4. In 1 year in 10 it comes by September 21.
What hardiness zone is 55370?
ZIP 55370 is in USDA zone 4b (-25 to -20°F average coldest winter night), per the 2023 USDA Plant Hardiness Zone Map ZIP listing.
What is the soil temperature in 55370 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
55397 55339 Hamburg 55354 Lester Prairie 55368 Norwood Young America 55338 Green Isle 55336 Glencoe 55367 New Germany 55360 Mayer
Other ZIP codes in McLeod County
55312 55336 55350 55354 55381 55385 55395 All McLeod County frost dates · Minnesota frost dates
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Weekly yard timing, plus frost and soil-temperature alerts for your ZIP code.
- Freeze alerts
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Free. One weekly email plus alerts when your ZIP has a frost or a soil-temperature change worth acting on. After you submit, Kit (our email provider) sends a confirmation email: check your email and click the link to confirm. You aren't subscribed until you do. We collect only your email address and ZIP, sent to Kit to deliver The Dial. Unsubscribe anytime.