Fall in zone 5aPhoto: Dietmar Rabich, CC BY-SA 4.0, via Wikimedia Commons
Frost dates for ZIP 49891 (Alger County, MI)
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, Chatham 1 SE, MI (9 miles away).
- Average last spring frostMay 2750% chance of a 32°F freeze after this date
- Average first fall frostSep 2850% chance of a 32°F freeze by this date
- Growing season (frost-free)124 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 18, 2026, from your frost dates, zone and soil temperature. Lawn timing · Vegetables · Pruning · Plants
Soil temperature now
2-inch depth
47°F Below 50°F
24-hour average · latest 47°F, as of Oct 18, 1:00 AM CDT
Measured at NOAA USCRN station Chatham 1 SE, 9 mi away. Daily averages: Thu 51°, Fri 50°, Sat 47°.
4-inch depth
48°F Below 50°F
24-hour average · latest 48°F, as of Oct 18, 1:00 AM CDT
Measured at NOAA USCRN station Chatham 1 SE, 9 mi away. Daily averages: Thu 52°, Fri 50°, Sat 48°.
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 49891 load here. You can also open the NWS forecast for this ZIP.
Pre-emergent
Soil is 48°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) | May 11 |
| 50% (the "average" last frost) | May 27 |
| 10% (cautious: only 1 year in 10 freezes later) | Jun 12 |
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 9 |
| 50% (the "average" first frost) | Sep 28 |
| 90% (late: most years have frozen by now) | Oct 12 |
Light frost, freeze and hard freeze
| Threshold | Last spring (50%) | First fall (50%) |
|---|---|---|
| 36°F (light frost possible on clear, calm nights) | n/a | n/a |
| 32°F (freeze) | May 27 | Sep 28 |
| 28°F (hard freeze) | May 12 | Oct 11 |
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 49891
Dates count from your average last spring frost (May 27) and first fall frost (Sep 28). 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 | Apr 1–15 | Jun 3–17 (transplant) | – |
| Pepper (sweet and hot) | Mar 18–Apr 1 | Jun 10–24 (transplant) | – |
| Eggplant | Mar 18–Apr 1 | Jun 10–24 (transplant) | – |
| Tomatillo | Apr 1–15 | Jun 3–17 (transplant) | – |
| Lettuce | Apr 1–15 | May 6–27 (transplant) Apr 29–Jun 10 (sow outdoors) | Aug 3–24 (transplant) Jul 20–Aug 17 (sowing) |
| Spinach | – | Apr 15–May 6 (sow outdoors) | Aug 3–24 (sowing) |
| Kale | Apr 1–15 | Apr 29–May 13 (transplant) Apr 29–May 13 (sow outdoors) | Jul 6–Aug 3 (transplant) Jun 22–Jul 20 (sowing) |
| Collards | Apr 1–15 | Apr 29–May 27 (transplant) Apr 29–May 27 (sow outdoors) | Jul 6–Aug 3 (transplant) Jun 22–Jul 20 (sowing) |
| Broccoli | Mar 18–Apr 1 | Apr 29–May 13 (transplant) | Jun 22–Jul 20 (transplant) |
| Cabbage | Mar 18–Apr 1 | Apr 29–May 13 (transplant) | Jun 22–Jul 20 (transplant) |
| Cauliflower | Mar 18–Apr 1 | May 13–27 (transplant) | Jun 22–Jul 20 (transplant) |
| Brussels sprouts | Mar 4–18 | Apr 29–May 13 (transplant) | Jun 8–29 (transplant) |
| Kohlrabi | Apr 1–15 | Apr 29–May 13 (transplant) Apr 29–May 13 (sow outdoors) | Jul 20–Aug 3 (sowing) |
| Bok choy / Asian greens | – | Apr 29–May 13 (sow outdoors) | Aug 3–17 (sowing) |
| Arugula | – | Apr 29–May 27 (sow outdoors) | Aug 3–31 (sowing) |
| Mustard greens | – | Apr 29–May 20 (sow outdoors) | Aug 3–17 (sowing) |
| Swiss chard | Apr 15–29 | May 13–Jun 3 (transplant) May 13–Jun 10 (sow outdoors) | Jul 20–Aug 3 (sowing) |
| Beet | – | Apr 29–May 27 (sow outdoors) | Jul 20–Aug 3 (sowing) |
| Carrot | – | May 6–Jun 3 (sow outdoors) | Jul 6–20 (sowing) |
| Radish | – | Apr 22–Jun 3 (sow outdoors) | Aug 17–31 (sowing) |
| Turnip | – | Apr 29–May 20 (sow outdoors) | Jul 20–Aug 3 (sowing) |
| Parsnip | – | May 6–27 (sow outdoors) | – |
| Pea (garden, snap, snow) | – | Apr 1–29 (sow outdoors) | Jul 6–20 (sowing) |
| Onion (bulbing) | Mar 4–18 | Apr 15–29 (transplant) | – |
| Green onion / scallion | – | Apr 15–May 13 (sow outdoors) | Jul 20–Aug 3 (sowing) |
| Leek | Mar 4–18 | Apr 29–May 13 (transplant) | – |
| Garlic | – | – | Aug 17–Sep 14 (sowing) |
| Shallot | – | Apr 15–29 (transplant) | Aug 17–Sep 14 (sowing) |
| Potato | – | Apr 29–May 13 (transplant) | Jun 8–22 (transplant) |
| Sweet potato | – | Jun 17–Jul 1 (transplant) | – |
| Sweet corn | – | Jun 3–17 (sow outdoors) | – |
| Bean, bush (snap) | – | Jun 3–17 (sow outdoors) | – |
| Bean, pole | – | Jun 3–17 (sow outdoors) | – |
| Lima bean | – | Jun 10–24 (sow outdoors) | – |
| Southern pea (cowpea, black-eyed pea) | – | Jun 17–Jul 8 (sow outdoors) | – |
| Cucumber | Apr 29–May 6 | Jun 3–17 (transplant) Jun 3–17 (sow outdoors) | – |
| Summer squash / zucchini | Apr 29–May 6 | Jun 3–17 (transplant) Jun 3–17 (sow outdoors) | – |
| Winter squash | Apr 29–May 6 | Jun 3–17 (transplant) Jun 3–17 (sow outdoors) | – |
| Pumpkin | – | Jun 3–17 (sow outdoors) | – |
| Watermelon | Apr 29–May 6 | Jun 10–24 (transplant) Jun 10–24 (sow outdoors) | – |
| Cantaloupe / muskmelon | Apr 29–May 6 | Jun 10–24 (transplant) Jun 10–24 (sow outdoors) | – |
| Okra | Apr 15–29 | Jun 10–24 (transplant) Jun 10–24 (sow outdoors) | – |
| Celery | Mar 4–18 | Jun 3–10 (transplant) | – |
| Basil | Apr 15–29 | Jun 3–17 (transplant) Jun 3–17 (sow outdoors) | – |
| Cilantro | – | May 13–Jun 10 (sow outdoors) | Aug 3–17 (sowing) |
| Parsley | Mar 18–Apr 1 | May 13–27 (transplant) May 6–27 (sow outdoors) | – |
| Dill | – | May 27–Jun 10 (sow outdoors) | Aug 3–17 (sowing) |
| Sunflower | – | May 27–Jun 10 (sow outdoors) | – |
| Asparagus (crowns) | – | Apr 29–May 13 (transplant) | – |
| Rhubarb (crowns) | – | Apr 29–May 13 (transplant) | – |
| Strawberry (plants) | – | Apr 29–May 13 (transplant) | Jul 20–Aug 17 (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: Chatham 1 SE, MI (NOAA GHCN-Daily ID USW00054810), elevation 875 ft, 9.3 miles from the ZIP's center point. NOAA completeness flag: R (representative, 10+ years).
Nearby stations
| Station | Distance | Last frost (50%) | First frost (50%) |
|---|---|---|---|
| Chatham EXP Farm 2, MI | 10 mi | May 30 | Sep 27 |
| Ki Sawyer Wwtp, MI | 19 mi | May 13 | Oct 2 |
| Munising, MI | 22 mi | May 16 | Oct 14 |
The average last-frost dates of these stations span 17 days, a rough guide to local variation. See data sources & methods.
Frost questions for 49891
When is the last frost in 49891?
The average (50% chance) last spring freeze of 32°F for ZIP 49891 is May 27. For a more cautious planting date, use June 12, when only 1 year in 10 still sees a later freeze.
When is the first frost in 49891?
The average first fall freeze is September 28. In 1 year in 10 it comes by September 9.
What hardiness zone is 49891?
ZIP 49891 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 49891 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
49816 Chatham 49826 49825 49885 49880 Rock 49833 49872 49822
Other ZIP codes in Alger County
49806 49816 49822 49825 49826 49839 49862 49884 All Alger County frost dates · Michigan 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.