Fall in zone 5bPhoto: Dietmar Rabich, CC BY-SA 4.0, via Wikimedia Commons
Frost dates for ZIP 50153 (Lynnville, IA)
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, Grinnell 3 SW, IA (11 miles away).
- Average last spring frostMay 350% chance of a 32°F freeze after this date
- Average first fall frostOct 650% chance of a 32°F freeze by this date
- Growing season (frost-free)155 daysmedian, 32°F threshold
- USDA hardiness zone5b-15 to -10°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
56°F 55°F or warmer
24-hour average · latest 56°F, as of Oct 18, 2:00 AM CDT
Estimate Not a measurement at this ZIP: distance-weighted average of Des Moines 17 E (25 mi), Ames (56 mi).
4-inch depth
58°F 55°F or warmer
24-hour average · latest 57°F, as of Oct 18, 2:00 AM CDT
Estimate Not a measurement at this ZIP: distance-weighted average of Des Moines 17 E (25 mi), Ames (56 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 50153 load here. You can also open the NWS forecast for this ZIP.
Pre-emergent
Soil is 58°F at 4 inches (estimated soil temperature, not a station reading). Fall pre-emergent (annual bluegrass, winter weeds): window open as soil cools through the 70s and 60s.
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 19 |
| 50% (the "average" last frost) | May 3 |
| 10% (cautious: only 1 year in 10 freezes later) | May 17 |
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 22 |
| 50% (the "average" first frost) | Oct 6 |
| 90% (late: most years have frozen by now) | Oct 20 |
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 27 |
| 32°F (freeze) | May 3 | Oct 6 |
| 28°F (hard freeze) | Apr 23 | 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 50153
Dates count from your average last spring frost (May 3) and first fall frost (Oct 6). 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 8–22 | May 10–24 (transplant) | – |
| Pepper (sweet and hot) | Feb 22–Mar 8 | May 17–31 (transplant) | – |
| Eggplant | Feb 22–Mar 8 | May 17–31 (transplant) | – |
| Tomatillo | Mar 8–22 | May 10–24 (transplant) | – |
| Lettuce | Mar 8–22 | Apr 12–May 3 (transplant) Apr 5–May 17 (sow outdoors) | Aug 11–Sep 1 (transplant) Jul 28–Aug 25 (sowing) |
| Spinach | – | Mar 22–Apr 12 (sow outdoors) | Aug 11–Sep 1 (sowing) |
| Kale | Mar 8–22 | Apr 5–19 (transplant) Apr 5–19 (sow outdoors) | Jul 14–Aug 11 (transplant) Jun 30–Jul 28 (sowing) |
| Collards | Mar 8–22 | Apr 5–May 3 (transplant) Apr 5–May 3 (sow outdoors) | Jul 14–Aug 11 (transplant) Jun 30–Jul 28 (sowing) |
| Broccoli | Feb 22–Mar 8 | Apr 5–19 (transplant) | Jun 30–Jul 28 (transplant) |
| Cabbage | Feb 22–Mar 8 | Apr 5–19 (transplant) | Jun 30–Jul 28 (transplant) |
| Cauliflower | Feb 22–Mar 8 | Apr 19–May 3 (transplant) | Jun 30–Jul 28 (transplant) |
| Brussels sprouts | Feb 8–22 | Apr 5–19 (transplant) | Jun 16–Jul 7 (transplant) |
| Kohlrabi | Mar 8–22 | Apr 5–19 (transplant) Apr 5–19 (sow outdoors) | Jul 28–Aug 11 (sowing) |
| Bok choy / Asian greens | – | Apr 5–19 (sow outdoors) | Aug 11–25 (sowing) |
| Arugula | – | Apr 5–May 3 (sow outdoors) | Aug 11–Sep 8 (sowing) |
| Mustard greens | – | Apr 5–26 (sow outdoors) | Aug 11–25 (sowing) |
| Swiss chard | Mar 22–Apr 5 | Apr 19–May 10 (transplant) Apr 19–May 17 (sow outdoors) | Jul 28–Aug 11 (sowing) |
| Beet | – | Apr 5–May 3 (sow outdoors) | Jul 28–Aug 11 (sowing) |
| Carrot | – | Apr 12–May 10 (sow outdoors) | Jul 14–28 (sowing) |
| Radish | – | Mar 29–May 10 (sow outdoors) | Aug 25–Sep 8 (sowing) |
| Turnip | – | Apr 5–26 (sow outdoors) | Jul 28–Aug 11 (sowing) |
| Parsnip | – | Apr 12–May 3 (sow outdoors) | – |
| Pea (garden, snap, snow) | – | Mar 8–Apr 5 (sow outdoors) | Jul 14–28 (sowing) |
| Onion (bulbing) | Feb 8–22 | Mar 22–Apr 5 (transplant) | – |
| Green onion / scallion | – | Mar 22–Apr 19 (sow outdoors) | Jul 28–Aug 11 (sowing) |
| Leek | Feb 8–22 | Apr 5–19 (transplant) | – |
| Garlic | – | – | Aug 25–Sep 22 (sowing) |
| Shallot | – | Mar 22–Apr 5 (transplant) | Aug 25–Sep 22 (sowing) |
| Potato | – | Apr 5–19 (transplant) | Jun 16–30 (transplant) |
| Sweet potato | – | May 24–Jun 7 (transplant) | – |
| Sweet corn | – | May 10–24 (sow outdoors) | – |
| Bean, bush (snap) | – | May 10–24 (sow outdoors) | – |
| Bean, pole | – | May 10–24 (sow outdoors) | – |
| Lima bean | – | May 17–31 (sow outdoors) | – |
| Southern pea (cowpea, black-eyed pea) | – | May 24–Jun 14 (sow outdoors) | – |
| Cucumber | Apr 5–12 | May 10–24 (transplant) May 10–24 (sow outdoors) | – |
| Summer squash / zucchini | Apr 5–12 | May 10–24 (transplant) May 10–24 (sow outdoors) | – |
| Winter squash | Apr 5–12 | May 10–24 (transplant) May 10–24 (sow outdoors) | – |
| Pumpkin | – | May 10–24 (sow outdoors) | – |
| Watermelon | Apr 5–12 | May 17–31 (transplant) May 17–31 (sow outdoors) | – |
| Cantaloupe / muskmelon | Apr 5–12 | May 17–31 (transplant) May 17–31 (sow outdoors) | – |
| Okra | Mar 22–Apr 5 | May 17–31 (transplant) May 17–31 (sow outdoors) | – |
| Celery | Feb 8–22 | May 10–17 (transplant) | – |
| Basil | Mar 22–Apr 5 | May 10–24 (transplant) May 10–24 (sow outdoors) | – |
| Cilantro | – | Apr 19–May 17 (sow outdoors) | Aug 11–25 (sowing) |
| Parsley | Feb 22–Mar 8 | Apr 19–May 3 (transplant) Apr 12–May 3 (sow outdoors) | – |
| Dill | – | May 3–17 (sow outdoors) | Aug 11–25 (sowing) |
| Sunflower | – | May 3–17 (sow outdoors) | – |
| Asparagus (crowns) | – | Apr 5–19 (transplant) | – |
| Rhubarb (crowns) | – | Apr 5–19 (transplant) | – |
| Strawberry (plants) | – | Apr 5–19 (transplant) | Jul 28–Aug 25 (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: Grinnell 3 SW, IA (NOAA GHCN-Daily ID USC00133473), elevation 905 ft, 10.5 miles from the ZIP's center point. NOAA completeness flag: S (standard, 24+ years).
Nearby stations
| Station | Distance | Last frost (50%) | First frost (50%) |
|---|---|---|---|
| Newton, IA | 15 mi | Apr 22 | Oct 17 |
| Oskaloosa, IA | 19 mi | Apr 21 | Oct 16 |
| Knoxville, IA | 23 mi | Apr 20 | Oct 19 |
The average last-frost dates of these stations span 14 days, a rough guide to local variation. See data sources & methods.
Frost questions for 50153
When is the last frost in 50153?
The average (50% chance) last spring freeze of 32°F for ZIP 50153 is May 3. For a more cautious planting date, use May 17, when only 1 year in 10 still sees a later freeze.
When is the first frost in 50153?
The average first fall freeze is October 6. In 1 year in 10 it comes by September 22.
What hardiness zone is 50153?
ZIP 50153 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 50153 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
50251 Sully 50242 Searsboro 50137 50232 Reasnor 50219 Pella 50112 Grinnell 50135 Kellogg 50207 New Sharon
Other ZIP codes in Jasper County
50028 50054 50127 50135 50137 50168 50170 50208 50228 50232 50251 All Jasper County frost dates · Iowa 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.