Fall in zone 4bPhoto: Dietmar Rabich, CC BY-SA 4.0, via Wikimedia Commons
Frost dates for ZIP 55804 (Duluth, 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, Duluth Harbor STN, MN (13 miles away).
- Average last spring frostMay 1450% chance of a 32°F freeze after this date
- Average first fall frostOct 1250% chance of a 32°F freeze by this date
- Growing season (frost-free)149 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
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 55804 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 24 |
| 50% (the "average" last frost) | May 14 |
| 10% (cautious: only 1 year in 10 freezes later) | Jun 1 |
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 25 |
| 50% (the "average" first frost) | Oct 12 |
| 90% (late: most years have frozen by now) | Oct 26 |
Light frost, freeze and hard freeze
| Threshold | Last spring (50%) | First fall (50%) |
|---|---|---|
| 36°F (light frost possible on clear, calm nights) | May 31 | Sep 30 |
| 32°F (freeze) | May 14 | Oct 12 |
| 28°F (hard freeze) | Apr 29 | Oct 25 |
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 55804
Dates count from your average last spring frost (May 14) and first fall frost (Oct 12). 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 19–Apr 2 | May 21–Jun 4 (transplant) | – |
| Pepper (sweet and hot) | Mar 5–19 | May 28–Jun 11 (transplant) | – |
| Eggplant | Mar 5–19 | May 28–Jun 11 (transplant) | – |
| Tomatillo | Mar 19–Apr 2 | May 21–Jun 4 (transplant) | – |
| Lettuce | Mar 19–Apr 2 | Apr 23–May 14 (transplant) Apr 16–May 28 (sow outdoors) | Aug 17–Sep 7 (transplant) Aug 3–31 (sowing) |
| Spinach | – | Apr 2–23 (sow outdoors) | Aug 17–Sep 7 (sowing) |
| Kale | Mar 19–Apr 2 | Apr 16–30 (transplant) Apr 16–30 (sow outdoors) | Jul 20–Aug 17 (transplant) Jul 6–Aug 3 (sowing) |
| Collards | Mar 19–Apr 2 | Apr 16–May 14 (transplant) Apr 16–May 14 (sow outdoors) | Jul 20–Aug 17 (transplant) Jul 6–Aug 3 (sowing) |
| Broccoli | Mar 5–19 | Apr 16–30 (transplant) | Jul 6–Aug 3 (transplant) |
| Cabbage | Mar 5–19 | Apr 16–30 (transplant) | Jul 6–Aug 3 (transplant) |
| Cauliflower | Mar 5–19 | Apr 30–May 14 (transplant) | Jul 6–Aug 3 (transplant) |
| Brussels sprouts | Feb 19–Mar 5 | Apr 16–30 (transplant) | Jun 22–Jul 13 (transplant) |
| Kohlrabi | Mar 19–Apr 2 | Apr 16–30 (transplant) Apr 16–30 (sow outdoors) | Aug 3–17 (sowing) |
| Bok choy / Asian greens | – | Apr 16–30 (sow outdoors) | Aug 17–31 (sowing) |
| Arugula | – | Apr 16–May 14 (sow outdoors) | Aug 17–Sep 14 (sowing) |
| Mustard greens | – | Apr 16–May 7 (sow outdoors) | Aug 17–31 (sowing) |
| Swiss chard | Apr 2–16 | Apr 30–May 21 (transplant) Apr 30–May 28 (sow outdoors) | Aug 3–17 (sowing) |
| Beet | – | Apr 16–May 14 (sow outdoors) | Aug 3–17 (sowing) |
| Carrot | – | Apr 23–May 21 (sow outdoors) | Jul 20–Aug 3 (sowing) |
| Radish | – | Apr 9–May 21 (sow outdoors) | Aug 31–Sep 14 (sowing) |
| Turnip | – | Apr 16–May 7 (sow outdoors) | Aug 3–17 (sowing) |
| Parsnip | – | Apr 23–May 14 (sow outdoors) | – |
| Pea (garden, snap, snow) | – | Mar 19–Apr 16 (sow outdoors) | Jul 20–Aug 3 (sowing) |
| Onion (bulbing) | Feb 19–Mar 5 | Apr 2–16 (transplant) | – |
| Green onion / scallion | – | Apr 2–30 (sow outdoors) | Aug 3–17 (sowing) |
| Leek | Feb 19–Mar 5 | Apr 16–30 (transplant) | – |
| Garlic | – | – | Aug 31–Sep 28 (sowing) |
| Shallot | – | Apr 2–16 (transplant) | Aug 31–Sep 28 (sowing) |
| Potato | – | Apr 16–30 (transplant) | Jun 22–Jul 6 (transplant) |
| Sweet potato | – | Jun 4–18 (transplant) | – |
| Sweet corn | – | May 21–Jun 4 (sow outdoors) | – |
| Bean, bush (snap) | – | May 21–Jun 4 (sow outdoors) | – |
| Bean, pole | – | May 21–Jun 4 (sow outdoors) | – |
| Lima bean | – | May 28–Jun 11 (sow outdoors) | – |
| Southern pea (cowpea, black-eyed pea) | – | Jun 4–25 (sow outdoors) | – |
| Cucumber | Apr 16–23 | May 21–Jun 4 (transplant) May 21–Jun 4 (sow outdoors) | – |
| Summer squash / zucchini | Apr 16–23 | May 21–Jun 4 (transplant) May 21–Jun 4 (sow outdoors) | – |
| Winter squash | Apr 16–23 | May 21–Jun 4 (transplant) May 21–Jun 4 (sow outdoors) | – |
| Pumpkin | – | May 21–Jun 4 (sow outdoors) | – |
| Watermelon | Apr 16–23 | May 28–Jun 11 (transplant) May 28–Jun 11 (sow outdoors) | – |
| Cantaloupe / muskmelon | Apr 16–23 | May 28–Jun 11 (transplant) May 28–Jun 11 (sow outdoors) | – |
| Okra | Apr 2–16 | May 28–Jun 11 (transplant) May 28–Jun 11 (sow outdoors) | – |
| Celery | Feb 19–Mar 5 | May 21–28 (transplant) | – |
| Basil | Apr 2–16 | May 21–Jun 4 (transplant) May 21–Jun 4 (sow outdoors) | – |
| Cilantro | – | Apr 30–May 28 (sow outdoors) | Aug 17–31 (sowing) |
| Parsley | Mar 5–19 | Apr 30–May 14 (transplant) Apr 23–May 14 (sow outdoors) | – |
| Dill | – | May 14–28 (sow outdoors) | Aug 17–31 (sowing) |
| Sunflower | – | May 14–28 (sow outdoors) | – |
| Asparagus (crowns) | – | Apr 16–30 (transplant) | – |
| Rhubarb (crowns) | – | Apr 16–30 (transplant) | – |
| Strawberry (plants) | – | Apr 16–30 (transplant) | Aug 3–31 (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: Duluth Harbor STN, MN (NOAA GHCN-Daily ID USC00212246), elevation 610 ft, 13.4 miles from the ZIP's center point. NOAA completeness flag: R (representative, 10+ years).
Nearby stations
| Station | Distance | Last frost (50%) | First frost (50%) |
|---|---|---|---|
| Island Lake 4E, MN | 9 mi | May 21 | Sep 27 |
| Two Harbors, MN | 14 mi | May 12 | Oct 6 |
| Duluth, MN | 14 mi | May 13 | Oct 1 |
The average last-frost dates of these stations span 9 days, a rough guide to local variation. See data sources & methods.
Frost questions for 55804
When is the last frost in 55804?
The average (50% chance) last spring freeze of 32°F for ZIP 55804 is May 14. For a more cautious planting date, use June 1, when only 1 year in 10 still sees a later freeze.
When is the first frost in 55804?
The average first fall freeze is October 12. In 1 year in 10 it comes by September 25.
What hardiness zone is 55804?
ZIP 55804 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 55804 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
55609 Knife River 55803 Rice Lake 55812 Duluth 55805 Duluth 55802 Duluth 55814 Hermantown 55806 Duluth 55811 Hermantown
Other ZIP codes in St. Louis County
55602 55702 55703 55705 55706 55708 55710 55711 55713 55717 55719 55723 55724 55725 55732 55734 55736 55738 55741 55746 55750 55751 55758 55763 All St. Louis 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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- Weekly yard to-dos
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.