Fall in zone 6aPhoto: Dietmar Rabich, CC BY-SA 4.0, via Wikimedia Commons
Frost dates for ZIP 97758 (Harney County, OR)
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, Squaw Butte-northern Great Bas, OR (3 miles away).
- Average last spring frostJun 1150% 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)107 daysmedian, 32°F threshold
- USDA hardiness zone6a-10 to -5°F avg. coldest night
Get The Dial for 97758
Frost and freeze alerts from the NWS forecast for 97758, the spring soil-temperature heads-up for pre-emergent, and a short weekly yard-timing email.
- 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.
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
50°F 50–55°F
24-hour average · latest 55°F, as of Oct 18, 1:00 AM CDT
Measured at NOAA USCRN station Riley 10 WSW, 4 mi away. Daily averages: Thu 52°, Fri 50°, Sat 50°.
4-inch depth
51°F 50–55°F
24-hour average · latest 54°F, as of Oct 18, 1:00 AM CDT
Measured at NOAA USCRN station Riley 10 WSW, 4 mi away. Daily averages: Thu 53°, Fri 51°, Sat 51°.
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 97758 load here. You can also open the NWS forecast for this ZIP.
Pre-emergent
Soil is 51°F at 4 inches. Fall pre-emergent window is mostly past. Next: spring, when soil reaches 50°F (typically 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 18 |
| 50% (the "average" last frost) | Jun 11 |
| 10% (cautious: only 1 year in 10 freezes later) | Jun 28 |
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 3 |
| 50% (the "average" first frost) | Sep 28 |
| 90% (late: most years have frozen by now) | Oct 13 |
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 11 | Sep 28 |
| 28°F (hard freeze) | May 24 | Oct 13 |
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 97758
Dates count from your average last spring frost (Jun 11) 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 16–30 | Jun 18–Jul 2 (transplant) | – |
| Pepper (sweet and hot) | Apr 2–16 | Jun 25–Jul 9 (transplant) | – |
| Eggplant | Apr 2–16 | Jun 25–Jul 9 (transplant) | – |
| Tomatillo | Apr 16–30 | Jun 18–Jul 2 (transplant) | – |
| Lettuce | Apr 16–30 | May 21–Jun 11 (transplant) May 14–Jun 25 (sow outdoors) | Aug 3–24 (transplant) Jul 20–Aug 17 (sowing) |
| Spinach | – | Apr 30–May 21 (sow outdoors) | Aug 3–24 (sowing) |
| Kale | Apr 16–30 | May 14–28 (transplant) May 14–28 (sow outdoors) | Jul 6–Aug 3 (transplant) Jun 22–Jul 20 (sowing) |
| Collards | Apr 16–30 | May 14–Jun 11 (transplant) May 14–Jun 11 (sow outdoors) | Jul 6–Aug 3 (transplant) Jun 22–Jul 20 (sowing) |
| Broccoli | Apr 2–16 | May 14–28 (transplant) | Jun 22–Jul 20 (transplant) |
| Cabbage | Apr 2–16 | May 14–28 (transplant) | Jun 22–Jul 20 (transplant) |
| Cauliflower | Apr 2–16 | May 28–Jun 11 (transplant) | Jun 22–Jul 20 (transplant) |
| Brussels sprouts | Mar 19–Apr 2 | May 14–28 (transplant) | Jun 8–29 (transplant) |
| Kohlrabi | Apr 16–30 | May 14–28 (transplant) May 14–28 (sow outdoors) | Jul 20–Aug 3 (sowing) |
| Bok choy / Asian greens | – | May 14–28 (sow outdoors) | Aug 3–17 (sowing) |
| Arugula | – | May 14–Jun 11 (sow outdoors) | Aug 3–31 (sowing) |
| Mustard greens | – | May 14–Jun 4 (sow outdoors) | Aug 3–17 (sowing) |
| Swiss chard | Apr 30–May 14 | May 28–Jun 18 (transplant) May 28–Jun 25 (sow outdoors) | Jul 20–Aug 3 (sowing) |
| Beet | – | May 14–Jun 11 (sow outdoors) | Jul 20–Aug 3 (sowing) |
| Carrot | – | May 21–Jun 18 (sow outdoors) | Jul 6–20 (sowing) |
| Radish | – | May 7–Jun 18 (sow outdoors) | Aug 17–31 (sowing) |
| Turnip | – | May 14–Jun 4 (sow outdoors) | Jul 20–Aug 3 (sowing) |
| Parsnip | – | May 21–Jun 11 (sow outdoors) | – |
| Pea (garden, snap, snow) | – | Apr 16–May 14 (sow outdoors) | Jul 6–20 (sowing) |
| Onion (bulbing) | Mar 19–Apr 2 | Apr 30–May 14 (transplant) | – |
| Green onion / scallion | – | Apr 30–May 28 (sow outdoors) | Jul 20–Aug 3 (sowing) |
| Leek | Mar 19–Apr 2 | May 14–28 (transplant) | – |
| Garlic | – | – | Aug 17–Sep 14 (sowing) |
| Shallot | – | Apr 30–May 14 (transplant) | Aug 17–Sep 14 (sowing) |
| Potato | – | May 14–28 (transplant) | Jun 8–22 (transplant) |
| Sweet potato | – | Jul 2–16 (transplant) | – |
| Sweet corn | – | Jun 18–Jul 2 (sow outdoors) | – |
| Bean, bush (snap) | – | Jun 18–Jul 2 (sow outdoors) | – |
| Bean, pole | – | Jun 18–Jul 2 (sow outdoors) | – |
| Lima bean | – | Jun 25–Jul 9 (sow outdoors) | – |
| Southern pea (cowpea, black-eyed pea) | – | Jul 2–23 (sow outdoors) | – |
| Cucumber | May 14–21 | Jun 18–Jul 2 (transplant) Jun 18–Jul 2 (sow outdoors) | – |
| Summer squash / zucchini | May 14–21 | Jun 18–Jul 2 (transplant) Jun 18–Jul 2 (sow outdoors) | – |
| Winter squash | May 14–21 | Jun 18–Jul 2 (transplant) Jun 18–Jul 2 (sow outdoors) | – |
| Pumpkin | – | Jun 18–Jul 2 (sow outdoors) | – |
| Watermelon | May 14–21 | Jun 25–Jul 9 (transplant) Jun 25–Jul 9 (sow outdoors) | – |
| Cantaloupe / muskmelon | May 14–21 | Jun 25–Jul 9 (transplant) Jun 25–Jul 9 (sow outdoors) | – |
| Okra | Apr 30–May 14 | Jun 25–Jul 9 (transplant) Jun 25–Jul 9 (sow outdoors) | – |
| Celery | Mar 19–Apr 2 | Jun 18–25 (transplant) | – |
| Basil | Apr 30–May 14 | Jun 18–Jul 2 (transplant) Jun 18–Jul 2 (sow outdoors) | – |
| Cilantro | – | May 28–Jun 25 (sow outdoors) | Aug 3–17 (sowing) |
| Parsley | Apr 2–16 | May 28–Jun 11 (transplant) May 21–Jun 11 (sow outdoors) | – |
| Dill | – | Jun 11–25 (sow outdoors) | Aug 3–17 (sowing) |
| Sunflower | – | Jun 11–25 (sow outdoors) | – |
| Asparagus (crowns) | – | May 14–28 (transplant) | – |
| Rhubarb (crowns) | – | May 14–28 (transplant) | – |
| Strawberry (plants) | – | May 14–28 (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: Squaw Butte-northern Great Bas, OR (NOAA GHCN-Daily ID USC00358029), elevation 4,660 ft, 3.5 miles from the ZIP's center point. NOAA completeness flag: R (representative, 10+ years).
Nearby stations
| Station | Distance | Last frost (50%) | First frost (50%) |
|---|---|---|---|
| Riley 10 WSW, OR | 4 mi | Jun 11 | Sep 11 |
| O O Rch, OR | 26 mi | Jun 11 | Sep 6 |
| Alkali Lake, OR | 35 mi | Jun 10 | Sep 14 |
The average last-frost dates of these stations span 1 days, a rough guide to local variation. See data sources & methods.
Frost questions for 97758
When is the last frost in 97758?
The average (50% chance) last spring freeze of 32°F for ZIP 97758 is June 11. For a more cautious planting date, use June 28, when only 1 year in 10 still sees a later freeze.
When is the first frost in 97758?
The average first fall freeze is September 28. In 1 year in 10 it comes by September 3.
What hardiness zone is 97758?
ZIP 97758 is in USDA zone 6a (-10 to -5°F average coldest winter night), per the 2023 USDA Plant Hardiness Zone Map ZIP listing.
What is the soil temperature in 97758 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
97738 Hines 97712 97641 97720 Burns 97751 97640 97752 97820 Canyon City
Other ZIP codes in Harney County
97710 97720 97721 97722 97732 97736 97738 97904 All Harney County frost dates · Oregon frost dates
Never miss a frost: get The Dial
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.