Fall in zone 4bPhoto: Dietmar Rabich, CC BY-SA 4.0, via Wikimedia Commons
Frost dates for ZIP 55309 (Big Lake, 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, Elk Rvr, MN (9 miles away).
- Average last spring frostMay 450% chance of a 32°F freeze after this date
- Average first fall frostOct 550% chance of a 32°F freeze by this date
- Growing season (frost-free)154 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
Measured at USDA NRCS SCAN station Crescent Lake #1, 11 mi away. Daily averages: Thu 53°, Fri 52°, Sat 48°.
4-inch depth
50°F 50–55°F
24-hour average · latest 51°F, as of Oct 18, 2:00 AM CDT
Measured at USDA NRCS SCAN station Crescent Lake #1, 11 mi away. Daily averages: Thu 54°, Fri 53°, Sat 50°.
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 55309 load here. You can also open the NWS forecast for this ZIP.
Pre-emergent
Soil is 50°F at 4 inches. 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 22 |
| 50% (the "average" last frost) | May 4 |
| 10% (cautious: only 1 year in 10 freezes later) | May 18 |
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 23 |
| 50% (the "average" first frost) | Oct 5 |
| 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 13 | Sep 28 |
| 32°F (freeze) | May 4 | Oct 5 |
| 28°F (hard freeze) | Apr 25 | Oct 17 |
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 55309
Dates count from your average last spring frost (May 4) and first fall frost (Oct 5). 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 9–23 | May 11–25 (transplant) | – |
| Pepper (sweet and hot) | Feb 23–Mar 9 | May 18–Jun 1 (transplant) | – |
| Eggplant | Feb 23–Mar 9 | May 18–Jun 1 (transplant) | – |
| Tomatillo | Mar 9–23 | May 11–25 (transplant) | – |
| Lettuce | Mar 9–23 | Apr 13–May 4 (transplant) Apr 6–May 18 (sow outdoors) | Aug 10–31 (transplant) Jul 27–Aug 24 (sowing) |
| Spinach | – | Mar 23–Apr 13 (sow outdoors) | Aug 10–31 (sowing) |
| Kale | Mar 9–23 | Apr 6–20 (transplant) Apr 6–20 (sow outdoors) | Jul 13–Aug 10 (transplant) Jun 29–Jul 27 (sowing) |
| Collards | Mar 9–23 | Apr 6–May 4 (transplant) Apr 6–May 4 (sow outdoors) | Jul 13–Aug 10 (transplant) Jun 29–Jul 27 (sowing) |
| Broccoli | Feb 23–Mar 9 | Apr 6–20 (transplant) | Jun 29–Jul 27 (transplant) |
| Cabbage | Feb 23–Mar 9 | Apr 6–20 (transplant) | Jun 29–Jul 27 (transplant) |
| Cauliflower | Feb 23–Mar 9 | Apr 20–May 4 (transplant) | Jun 29–Jul 27 (transplant) |
| Brussels sprouts | Feb 9–23 | Apr 6–20 (transplant) | Jun 15–Jul 6 (transplant) |
| Kohlrabi | Mar 9–23 | Apr 6–20 (transplant) Apr 6–20 (sow outdoors) | Jul 27–Aug 10 (sowing) |
| Bok choy / Asian greens | – | Apr 6–20 (sow outdoors) | Aug 10–24 (sowing) |
| Arugula | – | Apr 6–May 4 (sow outdoors) | Aug 10–Sep 7 (sowing) |
| Mustard greens | – | Apr 6–27 (sow outdoors) | Aug 10–24 (sowing) |
| Swiss chard | Mar 23–Apr 6 | Apr 20–May 11 (transplant) Apr 20–May 18 (sow outdoors) | Jul 27–Aug 10 (sowing) |
| Beet | – | Apr 6–May 4 (sow outdoors) | Jul 27–Aug 10 (sowing) |
| Carrot | – | Apr 13–May 11 (sow outdoors) | Jul 13–27 (sowing) |
| Radish | – | Mar 30–May 11 (sow outdoors) | Aug 24–Sep 7 (sowing) |
| Turnip | – | Apr 6–27 (sow outdoors) | Jul 27–Aug 10 (sowing) |
| Parsnip | – | Apr 13–May 4 (sow outdoors) | – |
| Pea (garden, snap, snow) | – | Mar 9–Apr 6 (sow outdoors) | Jul 13–27 (sowing) |
| Onion (bulbing) | Feb 9–23 | Mar 23–Apr 6 (transplant) | – |
| Green onion / scallion | – | Mar 23–Apr 20 (sow outdoors) | Jul 27–Aug 10 (sowing) |
| Leek | Feb 9–23 | Apr 6–20 (transplant) | – |
| Garlic | – | – | Aug 24–Sep 21 (sowing) |
| Shallot | – | Mar 23–Apr 6 (transplant) | Aug 24–Sep 21 (sowing) |
| Potato | – | Apr 6–20 (transplant) | Jun 15–29 (transplant) |
| Sweet potato | – | May 25–Jun 8 (transplant) | – |
| Sweet corn | – | May 11–25 (sow outdoors) | – |
| Bean, bush (snap) | – | May 11–25 (sow outdoors) | – |
| Bean, pole | – | May 11–25 (sow outdoors) | – |
| Lima bean | – | May 18–Jun 1 (sow outdoors) | – |
| Southern pea (cowpea, black-eyed pea) | – | May 25–Jun 15 (sow outdoors) | – |
| Cucumber | Apr 6–13 | May 11–25 (transplant) May 11–25 (sow outdoors) | – |
| Summer squash / zucchini | Apr 6–13 | May 11–25 (transplant) May 11–25 (sow outdoors) | – |
| Winter squash | Apr 6–13 | May 11–25 (transplant) May 11–25 (sow outdoors) | – |
| Pumpkin | – | May 11–25 (sow outdoors) | – |
| Watermelon | Apr 6–13 | May 18–Jun 1 (transplant) May 18–Jun 1 (sow outdoors) | – |
| Cantaloupe / muskmelon | Apr 6–13 | May 18–Jun 1 (transplant) May 18–Jun 1 (sow outdoors) | – |
| Okra | Mar 23–Apr 6 | May 18–Jun 1 (transplant) May 18–Jun 1 (sow outdoors) | – |
| Celery | Feb 9–23 | May 11–18 (transplant) | – |
| Basil | Mar 23–Apr 6 | May 11–25 (transplant) May 11–25 (sow outdoors) | – |
| Cilantro | – | Apr 20–May 18 (sow outdoors) | Aug 10–24 (sowing) |
| Parsley | Feb 23–Mar 9 | Apr 20–May 4 (transplant) Apr 13–May 4 (sow outdoors) | – |
| Dill | – | May 4–18 (sow outdoors) | Aug 10–24 (sowing) |
| Sunflower | – | May 4–18 (sow outdoors) | – |
| Asparagus (crowns) | – | Apr 6–20 (transplant) | – |
| Rhubarb (crowns) | – | Apr 6–20 (transplant) | – |
| Strawberry (plants) | – | Apr 6–20 (transplant) | Jul 27–Aug 24 (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: Elk Rvr, MN (NOAA GHCN-Daily ID USC00212500), elevation 880 ft, 8.9 miles from the ZIP's center point. NOAA completeness flag: R (representative, 10+ years).
Nearby stations
| Station | Distance | Last frost (50%) | First frost (50%) |
|---|---|---|---|
| Santiago 3 E, MN | 12 mi | May 7 | Sep 28 |
| Buffalo 2NE, MN | 14 mi | Apr 30 | Oct 9 |
| St Cloud Rgnl AP, MN | 19 mi | May 7 | Sep 30 |
The average last-frost dates of these stations span 8 days, a rough guide to local variation. See data sources & methods.
Frost questions for 55309
When is the last frost in 55309?
The average (50% chance) last spring freeze of 32°F for ZIP 55309 is May 4. For a more cautious planting date, use May 18, when only 1 year in 10 still sees a later freeze.
When is the first frost in 55309?
The average first fall freeze is October 5. In 1 year in 10 it comes by September 23.
What hardiness zone is 55309?
ZIP 55309 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 55309 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
55308 Becker 55362 Monticello 55330 Elk River 55398 Zimmerman 55301 Albertville 55376 St. Michael 55319 Clear Lake 55313 Buffalo
Other ZIP codes in Sherburne County
55308 55319 55330 55398 56304 All Sherburne 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.