Frost dates for ZIP 99009 (Spokane County, WA)
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, Deer Park AP, WA (9 miles away).
- Average last spring frostMay 2250% chance of a 32°F freeze after this date
- Average first fall frostSep 1450% chance of a 32°F freeze by this date
- Growing season (frost-free)112 daysmedian, 32°F threshold
- USDA hardiness zone6b-5 to 0°F avg. coldest night
Get The Dial for 99009
Frost and freeze alerts from the NWS forecast for 99009, the spring soil-temperature heads-up for pre-emergent, and a short weekly yard-timing email.
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 17, 2026, from your frost dates, zone and soil temperature. Lawn timing · Vegetables · Pruning · Plants
Soil temperature now
2-inch depth
46°F Below 50°F
24-hour average · latest 50°F, as of Oct 17, 9:00 PM CDT
Estimate Not a measurement at this ZIP: distance-weighted average of Spokane 17 SSW (44 mi).
4-inch depth
47°F Below 50°F
24-hour average · latest 49°F, as of Oct 17, 9:00 PM CDT
Estimate Not a measurement at this ZIP: distance-weighted average of Spokane 17 SSW (44 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 99009 load here. You can also open the NWS forecast for this ZIP.
Pre-emergent
Soil is 47°F at 4 inches (estimated soil temperature, not a station reading). 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 2 |
| 50% (the "average" last frost) | May 22 |
| 10% (cautious: only 1 year in 10 freezes later) | Jun 15 |
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 28 |
| 50% (the "average" first frost) | Sep 14 |
| 90% (late: most years have frozen by now) | Oct 1 |
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 22 | Sep 14 |
| 28°F (hard freeze) | May 3 | Sep 29 |
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 99009
Dates count from your average last spring frost (May 22) and first fall frost (Sep 14). 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 27–Apr 10 | May 29–Jun 12 (transplant) | – |
| Pepper (sweet and hot) | Mar 13–27 | Jun 5–19 (transplant) | – |
| Eggplant | Mar 13–27 | Jun 5–19 (transplant) | – |
| Tomatillo | Mar 27–Apr 10 | May 29–Jun 12 (transplant) | – |
| Lettuce | Mar 27–Apr 10 | May 1–22 (transplant) Apr 24–Jun 5 (sow outdoors) | Jul 20–Aug 10 (transplant) Jul 6–Aug 3 (sowing) |
| Spinach | – | Apr 10–May 1 (sow outdoors) | Jul 20–Aug 10 (sowing) |
| Kale | Mar 27–Apr 10 | Apr 24–May 8 (transplant) Apr 24–May 8 (sow outdoors) | Jun 22–Jul 20 (transplant) Jun 8–Jul 6 (sowing) |
| Collards | Mar 27–Apr 10 | Apr 24–May 22 (transplant) Apr 24–May 22 (sow outdoors) | Jun 22–Jul 20 (transplant) Jun 8–Jul 6 (sowing) |
| Broccoli | Mar 13–27 | Apr 24–May 8 (transplant) | Jun 8–Jul 6 (transplant) |
| Cabbage | Mar 13–27 | Apr 24–May 8 (transplant) | Jun 8–Jul 6 (transplant) |
| Cauliflower | Mar 13–27 | May 8–22 (transplant) | Jun 8–Jul 6 (transplant) |
| Brussels sprouts | Feb 27–Mar 13 | Apr 24–May 8 (transplant) | May 25–Jun 15 (transplant) |
| Kohlrabi | Mar 27–Apr 10 | Apr 24–May 8 (transplant) Apr 24–May 8 (sow outdoors) | Jul 6–20 (sowing) |
| Bok choy / Asian greens | – | Apr 24–May 8 (sow outdoors) | Jul 20–Aug 3 (sowing) |
| Arugula | – | Apr 24–May 22 (sow outdoors) | Jul 20–Aug 17 (sowing) |
| Mustard greens | – | Apr 24–May 15 (sow outdoors) | Jul 20–Aug 3 (sowing) |
| Swiss chard | Apr 10–24 | May 8–29 (transplant) May 8–Jun 5 (sow outdoors) | Jul 6–20 (sowing) |
| Beet | – | Apr 24–May 22 (sow outdoors) | Jul 6–20 (sowing) |
| Carrot | – | May 1–29 (sow outdoors) | Jun 22–Jul 6 (sowing) |
| Radish | – | Apr 17–May 29 (sow outdoors) | Aug 3–17 (sowing) |
| Turnip | – | Apr 24–May 15 (sow outdoors) | Jul 6–20 (sowing) |
| Parsnip | – | May 1–22 (sow outdoors) | – |
| Pea (garden, snap, snow) | – | Mar 27–Apr 24 (sow outdoors) | Jun 22–Jul 6 (sowing) |
| Onion (bulbing) | Feb 27–Mar 13 | Apr 10–24 (transplant) | – |
| Green onion / scallion | – | Apr 10–May 8 (sow outdoors) | Jul 6–20 (sowing) |
| Leek | Feb 27–Mar 13 | Apr 24–May 8 (transplant) | – |
| Garlic | – | – | Aug 3–31 (sowing) |
| Shallot | – | Apr 10–24 (transplant) | Aug 3–31 (sowing) |
| Potato | – | Apr 24–May 8 (transplant) | May 25–Jun 8 (transplant) |
| Sweet potato | – | Jun 12–26 (transplant) | – |
| Sweet corn | – | May 29–Jun 12 (sow outdoors) | – |
| Bean, bush (snap) | – | May 29–Jun 12 (sow outdoors) | – |
| Bean, pole | – | May 29–Jun 12 (sow outdoors) | – |
| Lima bean | – | Jun 5–19 (sow outdoors) | – |
| Southern pea (cowpea, black-eyed pea) | – | Jun 12–Jul 3 (sow outdoors) | – |
| Cucumber | Apr 24–May 1 | May 29–Jun 12 (transplant) May 29–Jun 12 (sow outdoors) | – |
| Summer squash / zucchini | Apr 24–May 1 | May 29–Jun 12 (transplant) May 29–Jun 12 (sow outdoors) | – |
| Winter squash | Apr 24–May 1 | May 29–Jun 12 (transplant) May 29–Jun 12 (sow outdoors) | – |
| Pumpkin | – | May 29–Jun 12 (sow outdoors) | – |
| Watermelon | Apr 24–May 1 | Jun 5–19 (transplant) Jun 5–19 (sow outdoors) | – |
| Cantaloupe / muskmelon | Apr 24–May 1 | Jun 5–19 (transplant) Jun 5–19 (sow outdoors) | – |
| Okra | Apr 10–24 | Jun 5–19 (transplant) Jun 5–19 (sow outdoors) | – |
| Celery | Feb 27–Mar 13 | May 29–Jun 5 (transplant) | – |
| Basil | Apr 10–24 | May 29–Jun 12 (transplant) May 29–Jun 12 (sow outdoors) | – |
| Cilantro | – | May 8–Jun 5 (sow outdoors) | Jul 20–Aug 3 (sowing) |
| Parsley | Mar 13–27 | May 8–22 (transplant) May 1–22 (sow outdoors) | – |
| Dill | – | May 22–Jun 5 (sow outdoors) | Jul 20–Aug 3 (sowing) |
| Sunflower | – | May 22–Jun 5 (sow outdoors) | – |
| Asparagus (crowns) | – | Apr 24–May 8 (transplant) | – |
| Rhubarb (crowns) | – | Apr 24–May 8 (transplant) | – |
| Strawberry (plants) | – | Apr 24–May 8 (transplant) | Jul 6–Aug 3 (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: Deer Park AP, WA (NOAA GHCN-Daily ID USW00094119), elevation 2,191 ft, 8.9 miles from the ZIP's center point. NOAA completeness flag: R (representative, 10+ years).
Nearby stations
| Station | Distance | Last frost (50%) | First frost (50%) |
|---|---|---|---|
| Newport, WA | 14 mi | May 12 | Sep 21 |
| Spokane Felts Fld, WA | 24 mi | Apr 26 | Oct 15 |
| Chewelah, WA | 28 mi | May 16 | Sep 15 |
The average last-frost dates of these stations span 27 days, a rough guide to local variation. See data sources & methods.
Frost questions for 99009
When is the last frost in 99009?
The average (50% chance) last spring freeze of 32°F for ZIP 99009 is May 22. For a more cautious planting date, use June 15, when only 1 year in 10 still sees a later freeze.
When is the first frost in 99009?
The average first fall freeze is September 14. In 1 year in 10 it comes by August 28.
What hardiness zone is 99009?
ZIP 99009 is in USDA zone 6b (-5 to 0°F average coldest winter night), per the 2023 USDA Plant Hardiness Zone Map ZIP listing.
What is the soil temperature in 99009 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
99003 99156 Newport 99021 Mead 99006 Deer Park 83804 Blanchard 99005 Green Bluff 99110 Clayton 83822 Oldtown
Other ZIP codes in Spokane County
99001 99003 99004 99005 99006 99011 99012 99014 99016 99018 99019 99020 99021 99022 99023 99025 99026 99027 99030 99031 99036 99037 99039 99201 All Spokane County frost dates · Washington frost dates
Never miss a frost: get The Dial
Weekly yard timing, plus frost and soil-temperature alerts for your ZIP code.
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.