Fall in zone 8bPhoto: George Chernilevsky, Public domain, via Wikimedia Commons
Frost dates for ZIP 97133 (North Plains, 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, Scappoose Ind AP, OR (9 miles away).
- Average last spring frostApr 1050% chance of a 32°F freeze after this date
- Average first fall frostNov 250% chance of a 32°F freeze by this date
- Growing season (frost-free)209 daysmedian, 32°F threshold
- USDA hardiness zone8b15 to 20°F avg. coldest night
Get The Dial for 97133 (North Plains)
Frost and freeze alerts from the NWS forecast for 97133, 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
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 97133 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 2: 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) | Mar 17 |
| 50% (the "average" last frost) | Apr 10 |
| 10% (cautious: only 1 year in 10 freezes later) | May 1 |
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 16 |
| 50% (the "average" first frost) | Nov 2 |
| 90% (late: most years have frozen by now) | Nov 23 |
Light frost, freeze and hard freeze
| Threshold | Last spring (50%) | First fall (50%) |
|---|---|---|
| 36°F (light frost possible on clear, calm nights) | Apr 30 | Oct 16 |
| 32°F (freeze) | Apr 10 | Nov 2 |
| 28°F (hard freeze) | Mar 3 | Nov 19 |
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 97133
Dates count from your average last spring frost (Apr 10) and first fall frost (Nov 2). 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 | Feb 13–27 | Apr 17–May 1 (transplant) | – |
| Pepper (sweet and hot) | Jan 30–Feb 13 | Apr 24–May 8 (transplant) | – |
| Eggplant | Jan 30–Feb 13 | Apr 24–May 8 (transplant) | – |
| Tomatillo | Feb 13–27 | Apr 17–May 1 (transplant) | – |
| Lettuce | Feb 13–27 | Mar 20–Apr 10 (transplant) Mar 13–Apr 24 (sow outdoors) | Sep 7–28 (transplant) Aug 24–Sep 21 (sowing) |
| Spinach | – | Feb 27–Mar 20 (sow outdoors) | Sep 7–28 (sowing) |
| Kale | Feb 13–27 | Mar 13–27 (transplant) Mar 13–27 (sow outdoors) | Aug 10–Sep 7 (transplant) Jul 27–Aug 24 (sowing) |
| Collards | Feb 13–27 | Mar 13–Apr 10 (transplant) Mar 13–Apr 10 (sow outdoors) | Aug 10–Sep 7 (transplant) Jul 27–Aug 24 (sowing) |
| Broccoli | Jan 30–Feb 13 | Mar 13–27 (transplant) | Jul 27–Aug 24 (transplant) |
| Cabbage | Jan 30–Feb 13 | Mar 13–27 (transplant) | Jul 27–Aug 24 (transplant) |
| Cauliflower | Jan 30–Feb 13 | Mar 27–Apr 10 (transplant) | Jul 27–Aug 24 (transplant) |
| Brussels sprouts | Jan 16–30 | Mar 13–27 (transplant) | Jul 13–Aug 3 (transplant) |
| Kohlrabi | Feb 13–27 | Mar 13–27 (transplant) Mar 13–27 (sow outdoors) | Aug 24–Sep 7 (sowing) |
| Bok choy / Asian greens | – | Mar 13–27 (sow outdoors) | Sep 7–21 (sowing) |
| Arugula | – | Mar 13–Apr 10 (sow outdoors) | Sep 7–Oct 5 (sowing) |
| Mustard greens | – | Mar 13–Apr 3 (sow outdoors) | Sep 7–21 (sowing) |
| Swiss chard | Feb 27–Mar 13 | Mar 27–Apr 17 (transplant) Mar 27–Apr 24 (sow outdoors) | Aug 24–Sep 7 (sowing) |
| Beet | – | Mar 13–Apr 10 (sow outdoors) | Aug 24–Sep 7 (sowing) |
| Carrot | – | Mar 20–Apr 17 (sow outdoors) | Aug 10–24 (sowing) |
| Radish | – | Mar 6–Apr 17 (sow outdoors) | Sep 21–Oct 5 (sowing) |
| Turnip | – | Mar 13–Apr 3 (sow outdoors) | Aug 24–Sep 7 (sowing) |
| Parsnip | – | Mar 20–Apr 10 (sow outdoors) | – |
| Pea (garden, snap, snow) | – | Feb 13–Mar 13 (sow outdoors) | Aug 10–24 (sowing) |
| Onion (bulbing) | Jan 16–30 | Feb 27–Mar 13 (transplant) | – |
| Green onion / scallion | – | Feb 27–Mar 27 (sow outdoors) | Aug 24–Sep 7 (sowing) |
| Leek | Jan 16–30 | Mar 13–27 (transplant) | – |
| Garlic | – | – | Sep 21–Oct 19 (sowing) |
| Shallot | – | Feb 27–Mar 13 (transplant) | Sep 21–Oct 19 (sowing) |
| Potato | – | Mar 13–27 (transplant) | Jul 13–27 (transplant) |
| Sweet potato | – | May 1–15 (transplant) | – |
| Sweet corn | – | Apr 17–May 1 (sow outdoors) | – |
| Bean, bush (snap) | – | Apr 17–May 1 (sow outdoors) | – |
| Bean, pole | – | Apr 17–May 1 (sow outdoors) | – |
| Lima bean | – | Apr 24–May 8 (sow outdoors) | – |
| Southern pea (cowpea, black-eyed pea) | – | May 1–22 (sow outdoors) | – |
| Cucumber | Mar 13–20 | Apr 17–May 1 (transplant) Apr 17–May 1 (sow outdoors) | – |
| Summer squash / zucchini | Mar 13–20 | Apr 17–May 1 (transplant) Apr 17–May 1 (sow outdoors) | – |
| Winter squash | Mar 13–20 | Apr 17–May 1 (transplant) Apr 17–May 1 (sow outdoors) | – |
| Pumpkin | – | Apr 17–May 1 (sow outdoors) | – |
| Watermelon | Mar 13–20 | Apr 24–May 8 (transplant) Apr 24–May 8 (sow outdoors) | – |
| Cantaloupe / muskmelon | Mar 13–20 | Apr 24–May 8 (transplant) Apr 24–May 8 (sow outdoors) | – |
| Okra | Feb 27–Mar 13 | Apr 24–May 8 (transplant) Apr 24–May 8 (sow outdoors) | – |
| Celery | Jan 16–30 | Apr 17–24 (transplant) | – |
| Basil | Feb 27–Mar 13 | Apr 17–May 1 (transplant) Apr 17–May 1 (sow outdoors) | – |
| Cilantro | – | Mar 27–Apr 24 (sow outdoors) | Sep 7–21 (sowing) |
| Parsley | Jan 30–Feb 13 | Mar 27–Apr 10 (transplant) Mar 20–Apr 10 (sow outdoors) | – |
| Dill | – | Apr 10–24 (sow outdoors) | Sep 7–21 (sowing) |
| Sunflower | – | Apr 10–24 (sow outdoors) | – |
| Asparagus (crowns) | – | Mar 13–27 (transplant) | – |
| Rhubarb (crowns) | – | Mar 13–27 (transplant) | – |
| Strawberry (plants) | – | Mar 13–27 (transplant) | Aug 24–Sep 21 (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: Scappoose Ind AP, OR (NOAA GHCN-Daily ID USW00004201), elevation 55 ft, 9.3 miles from the ZIP's center point. NOAA completeness flag: R (representative, 10+ years).
Nearby stations
| Station | Distance | Last frost (50%) | First frost (50%) |
|---|---|---|---|
| Portland-hillsboro AP, OR | 11 mi | Apr 16 | Oct 23 |
| Forest Grove, OR | 12 mi | Apr 16 | Oct 26 |
| Saint Helens Rfd, OR | 13 mi | Apr 18 | Nov 7 |
The average last-frost dates of these stations span 8 days, a rough guide to local variation. See data sources & methods.
Frost questions for 97133
When is the last frost in 97133?
The average (50% chance) last spring freeze of 32°F for ZIP 97133 is April 10. For a more cautious planting date, use May 1, when only 1 year in 10 still sees a later freeze.
When is the first frost in 97133?
The average first fall freeze is November 2. In 1 year in 10 it comes by October 16.
What hardiness zone is 97133?
ZIP 97133 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 97133 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
97106 Banks 97056 Scappoose 97124 Hillsboro 97231 Portland 97109 97125 97116 Forest Grove 97053 Warren
Other ZIP codes in Washington County
97003 97005 97006 97007 97008 97062 97078 97106 97109 97113 97116 97117 97119 97123 97124 97125 97140 97144 97223 97224 97225 97229 All Washington 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.