Fall in zone 8bPhoto: George Chernilevsky, Public domain, via Wikimedia Commons
Frost dates for ZIP 97070 (Wilsonville, 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, N Willamette EXP STN, OR (2 miles away).
- Average last spring frostMar 1850% chance of a 32°F freeze after this date
- Average first fall frostNov 1350% chance of a 32°F freeze by this date
- Growing season (frost-free)243 daysmedian, 32°F threshold
- USDA hardiness zone8b15 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 97070 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 March to April.
Fertilizer window
Lawn region: Pacific Northwest (west of the Cascades). Timing only; always follow the product label.
- Perennial ryegrass (cool-season): Early fall: September; Late fall: October–November; Overseeded Bermuda: Light feeding once the winter rye is established, if needed. Avoid: Summer feeding.
Plant now
Prune now
No frost-timed pruning windows are open this week.
Your average first frost is Nov 13: 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) | Feb 22 |
| 50% (the "average" last frost) | Mar 18 |
| 10% (cautious: only 1 year in 10 freezes later) | Apr 10 |
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 27 |
| 50% (the "average" first frost) | Nov 13 |
| 90% (late: most years have frozen by now) | Dec 6 |
Light frost, freeze and hard freeze
| Threshold | Last spring (50%) | First fall (50%) |
|---|---|---|
| 36°F (light frost possible on clear, calm nights) | Apr 17 | Oct 27 |
| 32°F (freeze) | Mar 18 | Nov 13 |
| 28°F (hard freeze) | Feb 13 | Dec 1 |
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 97070
Dates count from your average last spring frost (Mar 18) and first fall frost (Nov 13). 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 | Jan 21–Feb 4 | Mar 25–Apr 8 (transplant) | Jul 17–Aug 14 (transplant) |
| Pepper (sweet and hot) | Jan 7–21 | Apr 1–15 (transplant) | Jul 24–Aug 14 (transplant) |
| Eggplant | Jan 7–21 | Apr 1–15 (transplant) | Jul 24–Aug 14 (transplant) |
| Tomatillo | Jan 21–Feb 4 | Mar 25–Apr 8 (transplant) | – |
| Lettuce | Jan 21–Feb 4 | Feb 25–Mar 18 (transplant) Feb 18–Apr 1 (sow outdoors) | Sep 18–Oct 9 (transplant) Sep 4–Oct 2 (sowing) |
| Spinach | – | Feb 4–25 (sow outdoors) | Sep 18–Oct 9 (sowing) |
| Kale | Jan 21–Feb 4 | Feb 18–Mar 4 (transplant) Feb 18–Mar 4 (sow outdoors) | Aug 21–Sep 18 (transplant) Aug 7–Sep 4 (sowing) |
| Collards | Jan 21–Feb 4 | Feb 18–Mar 18 (transplant) Feb 18–Mar 18 (sow outdoors) | Aug 21–Sep 18 (transplant) Aug 7–Sep 4 (sowing) |
| Broccoli | Jan 7–21 | Feb 18–Mar 4 (transplant) | Aug 7–Sep 4 (transplant) |
| Cabbage | Jan 7–21 | Feb 18–Mar 4 (transplant) | Aug 7–Sep 4 (transplant) |
| Cauliflower | Jan 7–21 | Mar 4–18 (transplant) | Aug 7–Sep 4 (transplant) |
| Brussels sprouts | Dec 24–Jan 7 | Feb 18–Mar 4 (transplant) | Jul 24–Aug 14 (transplant) |
| Kohlrabi | Jan 21–Feb 4 | Feb 18–Mar 4 (transplant) Feb 18–Mar 4 (sow outdoors) | Sep 4–18 (sowing) |
| Bok choy / Asian greens | – | Feb 18–Mar 4 (sow outdoors) | Sep 18–Oct 2 (sowing) |
| Arugula | – | Feb 18–Mar 18 (sow outdoors) | Sep 18–Oct 16 (sowing) |
| Mustard greens | – | Feb 18–Mar 11 (sow outdoors) | Sep 18–Oct 2 (sowing) |
| Swiss chard | Feb 4–18 | Mar 4–25 (transplant) Mar 4–Apr 1 (sow outdoors) | Sep 4–18 (sowing) |
| Beet | – | Feb 18–Mar 18 (sow outdoors) | Sep 4–18 (sowing) |
| Carrot | – | Feb 25–Mar 25 (sow outdoors) | Aug 21–Sep 4 (sowing) |
| Radish | – | Feb 11–Mar 25 (sow outdoors) | Oct 2–16 (sowing) |
| Turnip | – | Feb 18–Mar 11 (sow outdoors) | Sep 4–18 (sowing) |
| Parsnip | – | Feb 25–Mar 18 (sow outdoors) | – |
| Pea (garden, snap, snow) | – | Jan 21–Feb 18 (sow outdoors) | Aug 21–Sep 4 (sowing) |
| Onion (bulbing) | Dec 24–Jan 7 | Feb 4–18 (transplant) | – |
| Green onion / scallion | – | Feb 4–Mar 4 (sow outdoors) | Sep 4–18 (sowing) |
| Leek | Dec 24–Jan 7 | Feb 18–Mar 4 (transplant) | – |
| Garlic | – | – | Oct 2–30 (sowing) |
| Shallot | – | Feb 4–18 (transplant) | Oct 2–30 (sowing) |
| Potato | – | Feb 18–Mar 4 (transplant) | Jul 24–Aug 7 (transplant) |
| Sweet potato | – | Apr 8–22 (transplant) | – |
| Sweet corn | – | Mar 25–Apr 8 (sow outdoors) | – |
| Bean, bush (snap) | – | Mar 25–Apr 8 (sow outdoors) | Aug 21–Sep 4 (sowing) |
| Bean, pole | – | Mar 25–Apr 8 (sow outdoors) | – |
| Lima bean | – | Apr 1–15 (sow outdoors) | – |
| Southern pea (cowpea, black-eyed pea) | – | Apr 8–29 (sow outdoors) | – |
| Cucumber | Feb 18–25 | Mar 25–Apr 8 (transplant) Mar 25–Apr 8 (sow outdoors) | Aug 21–Sep 4 (sowing) |
| Summer squash / zucchini | Feb 18–25 | Mar 25–Apr 8 (transplant) Mar 25–Apr 8 (sow outdoors) | Aug 21–Sep 4 (sowing) |
| Winter squash | Feb 18–25 | Mar 25–Apr 8 (transplant) Mar 25–Apr 8 (sow outdoors) | – |
| Pumpkin | – | Mar 25–Apr 8 (sow outdoors) | – |
| Watermelon | Feb 18–25 | Apr 1–15 (transplant) Apr 1–15 (sow outdoors) | – |
| Cantaloupe / muskmelon | Feb 18–25 | Apr 1–15 (transplant) Apr 1–15 (sow outdoors) | – |
| Okra | Feb 4–18 | Apr 1–15 (transplant) Apr 1–15 (sow outdoors) | – |
| Celery | Dec 24–Jan 7 | Mar 25–Apr 1 (transplant) | – |
| Basil | Feb 4–18 | Mar 25–Apr 8 (transplant) Mar 25–Apr 8 (sow outdoors) | – |
| Cilantro | – | Mar 4–Apr 1 (sow outdoors) | Sep 18–Oct 2 (sowing) |
| Parsley | Jan 7–21 | Mar 4–18 (transplant) Feb 25–Mar 18 (sow outdoors) | – |
| Dill | – | Mar 18–Apr 1 (sow outdoors) | Sep 18–Oct 2 (sowing) |
| Sunflower | – | Mar 18–Apr 1 (sow outdoors) | – |
| Asparagus (crowns) | – | Feb 18–Mar 4 (transplant) | – |
| Rhubarb (crowns) | – | Feb 18–Mar 4 (transplant) | – |
| Strawberry (plants) | – | Feb 18–Mar 4 (transplant) | Sep 4–Oct 2 (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: N Willamette EXP STN, OR (NOAA GHCN-Daily ID USC00356151), elevation 150 ft, 2.1 miles from the ZIP's center point. NOAA completeness flag: R (representative, 10+ years).
Nearby stations
| Station | Distance | Last frost (50%) | First frost (50%) |
|---|---|---|---|
| Aurora State AP, OR | 4 mi | Mar 16 | Nov 14 |
| Rex 1 S, OR | 7 mi | Mar 21 | Nov 22 |
| Oregon City, OR | 9 mi | Mar 18 | Nov 18 |
The average last-frost dates of these stations span 5 days, a rough guide to local variation. See data sources & methods.
Frost questions for 97070
When is the last frost in 97070?
The average (50% chance) last spring freeze of 32°F for ZIP 97070 is March 18. For a more cautious planting date, use April 10, when only 1 year in 10 still sees a later freeze.
When is the first frost in 97070?
The average first fall freeze is November 13. In 1 year in 10 it comes by October 27.
What hardiness zone is 97070?
ZIP 97070 is in USDA zone 8b (15 to 20°F average coldest winter night), per the 2023 USDA Plant Hardiness Zone Map ZIP listing.
What is the soil temperature in 97070 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
97062 Tualatin 97002 Butteville 97140 Sherwood 97068 West Linn 97020 Donald 97224 Tigard 97035 Lake Oswego 97013 Canby
Other ZIP codes in Clackamas County
97004 97009 97011 97013 97015 97017 97022 97023 97027 97028 97034 97035 97038 97042 97045 97049 97055 97067 97068 97086 97089 97222 97267 All Clackamas County frost dates · Oregon 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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- 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.