Fall in zone 4bPhoto: Dietmar Rabich, CC BY-SA 4.0, via Wikimedia Commons
Frost dates for ZIP 59410 (Augusta, MT)
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, Gibson Dam, MT (8 miles away).
- Average last spring frostJun 1250% chance of a 32°F freeze after this date
- Average first fall frostSep 850% chance of a 32°F freeze by this date
- Growing season (frost-free)88 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 59410 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 mid-May.
Fertilizer window
Lawn region: Mountain West and High Plains. 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 25 |
| 50% (the "average" last frost) | Jun 12 |
| 10% (cautious: only 1 year in 10 freezes later) | Jul 5 |
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) | Aug 23 |
| 50% (the "average" first frost) | Sep 8 |
| 90% (late: most years have frozen by now) | Sep 24 |
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) | Jun 12 | Sep 8 |
| 28°F (hard freeze) | May 19 | Sep 24 |
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 59410
Dates count from your average last spring frost (Jun 12) and first fall frost (Sep 8). 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 17–May 1 | Jun 19–Jul 3 (transplant) | – |
| Pepper (sweet and hot) | Apr 3–17 | Jun 26–Jul 10 (transplant) | – |
| Eggplant | Apr 3–17 | Jun 26–Jul 10 (transplant) | – |
| Tomatillo | Apr 17–May 1 | Jun 19–Jul 3 (transplant) | – |
| Lettuce | Apr 17–May 1 | May 22–Jun 12 (transplant) May 15–Jun 26 (sow outdoors) | Jul 14–Aug 4 (transplant) Jun 30–Jul 28 (sowing) |
| Spinach | – | May 1–22 (sow outdoors) | Jul 14–Aug 4 (sowing) |
| Kale | Apr 17–May 1 | May 15–29 (transplant) May 15–29 (sow outdoors) | Jun 16–Jul 14 (transplant) Jun 2–30 (sowing) |
| Collards | Apr 17–May 1 | May 15–Jun 12 (transplant) May 15–Jun 12 (sow outdoors) | Jun 16–Jul 14 (transplant) |
| Broccoli | Apr 3–17 | May 15–29 (transplant) | Jun 2–30 (transplant) |
| Cabbage | Apr 3–17 | May 15–29 (transplant) | Jun 2–30 (transplant) |
| Cauliflower | Apr 3–17 | May 29–Jun 12 (transplant) | – |
| Brussels sprouts | Mar 20–Apr 3 | May 15–29 (transplant) | – |
| Kohlrabi | Apr 17–May 1 | May 15–29 (transplant) May 15–29 (sow outdoors) | Jun 30–Jul 14 (sowing) |
| Bok choy / Asian greens | – | May 15–29 (sow outdoors) | Jul 14–28 (sowing) |
| Arugula | – | May 15–Jun 12 (sow outdoors) | Jul 14–Aug 11 (sowing) |
| Mustard greens | – | May 15–Jun 5 (sow outdoors) | Jul 14–28 (sowing) |
| Swiss chard | May 1–15 | May 29–Jun 19 (transplant) May 29–Jun 26 (sow outdoors) | Jun 30–Jul 14 (sowing) |
| Beet | – | May 15–Jun 12 (sow outdoors) | Jun 30–Jul 14 (sowing) |
| Carrot | – | May 22–Jun 19 (sow outdoors) | – |
| Radish | – | May 8–Jun 19 (sow outdoors) | Jul 28–Aug 11 (sowing) |
| Turnip | – | May 15–Jun 5 (sow outdoors) | Jun 30–Jul 14 (sowing) |
| Parsnip | – | May 22–Jun 12 (sow outdoors) | – |
| Pea (garden, snap, snow) | – | Apr 17–May 15 (sow outdoors) | Jun 16–30 (sowing) |
| Onion (bulbing) | Mar 20–Apr 3 | May 1–15 (transplant) | – |
| Green onion / scallion | – | May 1–29 (sow outdoors) | Jun 30–Jul 14 (sowing) |
| Leek | Mar 20–Apr 3 | May 15–29 (transplant) | – |
| Garlic | – | – | Jul 28–Aug 25 (sowing) |
| Shallot | – | May 1–15 (transplant) | Jul 28–Aug 25 (sowing) |
| Potato | – | May 15–29 (transplant) | – |
| Sweet potato | – | Jul 3–17 (transplant) | – |
| Sweet corn | – | Jun 19–Jul 3 (sow outdoors) | – |
| Bean, bush (snap) | – | Jun 19–Jul 3 (sow outdoors) | – |
| Bean, pole | – | Jun 19–Jul 3 (sow outdoors) | – |
| Lima bean | – | Jun 26–Jul 10 (sow outdoors) | – |
| Southern pea (cowpea, black-eyed pea) | – | Jul 3–24 (sow outdoors) | – |
| Cucumber | May 15–22 | Jun 19–Jul 3 (transplant) Jun 19–Jul 3 (sow outdoors) | – |
| Summer squash / zucchini | May 15–22 | Jun 19–Jul 3 (transplant) Jun 19–Jul 3 (sow outdoors) | – |
| Winter squash | May 15–22 | Jun 19–Jul 3 (transplant) Jun 19–Jul 3 (sow outdoors) | – |
| Pumpkin | – | Jun 19–Jul 3 (sow outdoors) | – |
| Watermelon | May 15–22 | Jun 26–Jul 10 (transplant) Jun 26–Jul 10 (sow outdoors) | – |
| Cantaloupe / muskmelon | May 15–22 | Jun 26–Jul 10 (transplant) Jun 26–Jul 10 (sow outdoors) | – |
| Okra | May 1–15 | Jun 26–Jul 10 (transplant) Jun 26–Jul 10 (sow outdoors) | – |
| Celery | Mar 20–Apr 3 | Jun 19–26 (transplant) | – |
| Basil | May 1–15 | Jun 19–Jul 3 (transplant) Jun 19–Jul 3 (sow outdoors) | – |
| Cilantro | – | May 29–Jun 26 (sow outdoors) | Jul 14–28 (sowing) |
| Parsley | Apr 3–17 | May 29–Jun 12 (transplant) May 22–Jun 12 (sow outdoors) | – |
| Dill | – | Jun 12–26 (sow outdoors) | Jul 14–28 (sowing) |
| Sunflower | – | Jun 12–26 (sow outdoors) | – |
| Asparagus (crowns) | – | May 15–29 (transplant) | – |
| Rhubarb (crowns) | – | May 15–29 (transplant) | – |
| Strawberry (plants) | – | May 15–29 (transplant) | Jun 30–Jul 28 (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: Gibson Dam, MT (NOAA GHCN-Daily ID USC00243489), elevation 4,590 ft, 8.4 miles from the ZIP's center point. NOAA completeness flag: R (representative, 10+ years).
Nearby stations
| Station | Distance | Last frost (50%) | First frost (50%) |
|---|---|---|---|
| Augusta, MT | 12 mi | May 19 | Sep 21 |
| Rogers Pass 9 NNE, MT | 27 mi | May 21 | Sep 15 |
| Choteau, MT | 30 mi | May 28 | Sep 12 |
The average last-frost dates of these stations span 24 days, a rough guide to local variation. See data sources & methods.
Frost questions for 59410
When is the last frost in 59410?
The average (50% chance) last spring freeze of 32°F for ZIP 59410 is June 12. For a more cautious planting date, use July 5, when only 1 year in 10 still sees a later freeze.
When is the first frost in 59410?
The average first fall freeze is September 8. In 1 year in 10 it comes by August 23.
What hardiness zone is 59410?
ZIP 59410 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 59410 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
59639 Lincoln 59422 New Rockport Colony 59436 Fairfield 59854 Ovando 59477 Simms 59648 Milford Colony 59419 Bynum 59443 Fort Shaw
Other ZIP codes in Lewis and Clark County
59601 59602 59623 59625 59633 59635 59636 59639 59640 59648 All Lewis and Clark County frost dates · Montana frost dates
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- 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.