Fall in zone 5bPhoto: Dietmar Rabich, CC BY-SA 4.0, via Wikimedia Commons
Frost dates for ZIP 46531 (Starke County, IN)
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, Knox Wwtp, IN (7 miles away).
- Average last spring frostApr 2650% chance of a 32°F freeze after this date
- Average first fall frostOct 1950% chance of a 32°F freeze by this date
- Growing season (frost-free)174 daysmedian, 32°F threshold
- USDA hardiness zone5b-15 to -10°F avg. coldest night
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Frost and freeze alerts from the NWS forecast for 46531, the spring soil-temperature heads-up for pre-emergent, and a short weekly yard-timing email.
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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 46531 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.
Your average first frost is Oct 19: skip heavy pruning in the 6–8 weeks before it, because new growth may not harden off in time.
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 12 |
| 50% (the "average" last frost) | Apr 26 |
| 10% (cautious: only 1 year in 10 freezes later) | May 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) | Oct 5 |
| 50% (the "average" first frost) | Oct 19 |
| 90% (late: most years have frozen by now) | Oct 31 |
Light frost, freeze and hard freeze
| Threshold | Last spring (50%) | First fall (50%) |
|---|---|---|
| 36°F (light frost possible on clear, calm nights) | May 6 | Oct 8 |
| 32°F (freeze) | Apr 26 | Oct 19 |
| 28°F (hard freeze) | Apr 15 | Oct 30 |
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 46531
Dates count from your average last spring frost (Apr 26) and first fall frost (Oct 19). 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 1–15 | May 3–17 (transplant) | – |
| Pepper (sweet and hot) | Feb 15–Mar 1 | May 10–24 (transplant) | – |
| Eggplant | Feb 15–Mar 1 | May 10–24 (transplant) | – |
| Tomatillo | Mar 1–15 | May 3–17 (transplant) | – |
| Lettuce | Mar 1–15 | Apr 5–26 (transplant) Mar 29–May 10 (sow outdoors) | Aug 24–Sep 14 (transplant) Aug 10–Sep 7 (sowing) |
| Spinach | – | Mar 15–Apr 5 (sow outdoors) | Aug 24–Sep 14 (sowing) |
| Kale | Mar 1–15 | Mar 29–Apr 12 (transplant) Mar 29–Apr 12 (sow outdoors) | Jul 27–Aug 24 (transplant) Jul 13–Aug 10 (sowing) |
| Collards | Mar 1–15 | Mar 29–Apr 26 (transplant) Mar 29–Apr 26 (sow outdoors) | Jul 27–Aug 24 (transplant) Jul 13–Aug 10 (sowing) |
| Broccoli | Feb 15–Mar 1 | Mar 29–Apr 12 (transplant) | Jul 13–Aug 10 (transplant) |
| Cabbage | Feb 15–Mar 1 | Mar 29–Apr 12 (transplant) | Jul 13–Aug 10 (transplant) |
| Cauliflower | Feb 15–Mar 1 | Apr 12–26 (transplant) | Jul 13–Aug 10 (transplant) |
| Brussels sprouts | Feb 1–15 | Mar 29–Apr 12 (transplant) | Jun 29–Jul 20 (transplant) |
| Kohlrabi | Mar 1–15 | Mar 29–Apr 12 (transplant) Mar 29–Apr 12 (sow outdoors) | Aug 10–24 (sowing) |
| Bok choy / Asian greens | – | Mar 29–Apr 12 (sow outdoors) | Aug 24–Sep 7 (sowing) |
| Arugula | – | Mar 29–Apr 26 (sow outdoors) | Aug 24–Sep 21 (sowing) |
| Mustard greens | – | Mar 29–Apr 19 (sow outdoors) | Aug 24–Sep 7 (sowing) |
| Swiss chard | Mar 15–29 | Apr 12–May 3 (transplant) Apr 12–May 10 (sow outdoors) | Aug 10–24 (sowing) |
| Beet | – | Mar 29–Apr 26 (sow outdoors) | Aug 10–24 (sowing) |
| Carrot | – | Apr 5–May 3 (sow outdoors) | Jul 27–Aug 10 (sowing) |
| Radish | – | Mar 22–May 3 (sow outdoors) | Sep 7–21 (sowing) |
| Turnip | – | Mar 29–Apr 19 (sow outdoors) | Aug 10–24 (sowing) |
| Parsnip | – | Apr 5–26 (sow outdoors) | – |
| Pea (garden, snap, snow) | – | Mar 1–29 (sow outdoors) | Jul 27–Aug 10 (sowing) |
| Onion (bulbing) | Feb 1–15 | Mar 15–29 (transplant) | – |
| Green onion / scallion | – | Mar 15–Apr 12 (sow outdoors) | Aug 10–24 (sowing) |
| Leek | Feb 1–15 | Mar 29–Apr 12 (transplant) | – |
| Garlic | – | – | Sep 7–Oct 5 (sowing) |
| Shallot | – | Mar 15–29 (transplant) | Sep 7–Oct 5 (sowing) |
| Potato | – | Mar 29–Apr 12 (transplant) | Jun 29–Jul 13 (transplant) |
| Sweet potato | – | May 17–31 (transplant) | – |
| Sweet corn | – | May 3–17 (sow outdoors) | – |
| Bean, bush (snap) | – | May 3–17 (sow outdoors) | – |
| Bean, pole | – | May 3–17 (sow outdoors) | – |
| Lima bean | – | May 10–24 (sow outdoors) | – |
| Southern pea (cowpea, black-eyed pea) | – | May 17–Jun 7 (sow outdoors) | – |
| Cucumber | Mar 29–Apr 5 | May 3–17 (transplant) May 3–17 (sow outdoors) | – |
| Summer squash / zucchini | Mar 29–Apr 5 | May 3–17 (transplant) May 3–17 (sow outdoors) | – |
| Winter squash | Mar 29–Apr 5 | May 3–17 (transplant) May 3–17 (sow outdoors) | – |
| Pumpkin | – | May 3–17 (sow outdoors) | – |
| Watermelon | Mar 29–Apr 5 | May 10–24 (transplant) May 10–24 (sow outdoors) | – |
| Cantaloupe / muskmelon | Mar 29–Apr 5 | May 10–24 (transplant) May 10–24 (sow outdoors) | – |
| Okra | Mar 15–29 | May 10–24 (transplant) May 10–24 (sow outdoors) | – |
| Celery | Feb 1–15 | May 3–10 (transplant) | – |
| Basil | Mar 15–29 | May 3–17 (transplant) May 3–17 (sow outdoors) | – |
| Cilantro | – | Apr 12–May 10 (sow outdoors) | Aug 24–Sep 7 (sowing) |
| Parsley | Feb 15–Mar 1 | Apr 12–26 (transplant) Apr 5–26 (sow outdoors) | – |
| Dill | – | Apr 26–May 10 (sow outdoors) | Aug 24–Sep 7 (sowing) |
| Sunflower | – | Apr 26–May 10 (sow outdoors) | – |
| Asparagus (crowns) | – | Mar 29–Apr 12 (transplant) | – |
| Rhubarb (crowns) | – | Mar 29–Apr 12 (transplant) | – |
| Strawberry (plants) | – | Mar 29–Apr 12 (transplant) | Aug 10–Sep 7 (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: Knox Wwtp, IN (NOAA GHCN-Daily ID USC00124657), elevation 690 ft, 6.7 miles from the ZIP's center point. NOAA completeness flag: R (representative, 10+ years).
Nearby stations
| Station | Distance | Last frost (50%) | First frost (50%) |
|---|---|---|---|
| Plymouth, IN | 10 mi | Apr 25 | Oct 21 |
| Lakeville, IN | 17 mi | May 1 | Oct 13 |
| Laporte, IN | 21 mi | Apr 19 | Oct 27 |
The average last-frost dates of these stations span 13 days, a rough guide to local variation. See data sources & methods.
Frost questions for 46531
When is the last frost in 46531?
The average (50% chance) last spring freeze of 32°F for ZIP 46531 is April 26. For a more cautious planting date, use May 12, when only 1 year in 10 still sees a later freeze.
When is the first frost in 46531?
The average first fall freeze is October 19. In 1 year in 10 it comes by October 5.
What hardiness zone is 46531?
ZIP 46531 is in USDA zone 5b (-15 to -10°F average coldest winter night), per the 2023 USDA Plant Hardiness Zone Map ZIP listing.
What is the soil temperature in 46531 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
46513 46532 Hamlet 46534 Bass Lake 46572 46574 Koontz Lake 46563 Plymouth 46511 Culver 46346 Kingsford Heights
Other ZIP codes in Starke County
46366 46374 46532 46534 All Starke County frost dates · Indiana frost dates
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Weekly yard timing, plus frost and soil-temperature alerts for your ZIP code.
- Freeze alerts
- Soil-temp heads-up
- 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.