USDA Hardiness Zone 8b
Frost Dates for 97071 — Woodburn, Oregon
Averages from Aurora State Ap, Or US, the nearest reporting station, 8.1 miles away.
Plant tender crops after March 16, and expect the first autumn freeze around November 14. That leaves about 242 frost-free days.
- Last spring frost
- March 16
- First fall frost
- November 14
- Growing season
- 242 days
- Hardiness zone
- 8b
50% probability
50% probability
frost-free
15 to 20°F annual low
Planting calendar for 97071
| When | What to do |
|---|---|
| January 5 – January 19 | Start peppers and aubergines indoors They need eight to ten weeks under lights before they can go out. |
| January 19 – February 2 | Start tomatoes indoors Six to eight weeks gives a transplant big enough to set fruit early. |
| February 16 – March 2 | Sow peas, spinach, lettuce, radish outdoors These tolerate light frost and prefer to germinate in cool soil. |
| March 16 onward | Transplant tomatoes, peppers, basil, squash, cucumbers The average last freeze has passed — still watch the actual forecast. |
| by August 22 | Sow the autumn crop of carrots, beets and brassicas They need about twelve weeks to size up before growth stops. |
| by October 31 | Harvest tender crops, or be ready to cover them A first freeze two weeks early is well within normal variation. |
| November 14 onward | Plant garlic, mulch beds, lift tender bulbs Garlic wants a cold spell; bare soil loses structure over winter. |
What these dates mean
Wait until after March 16 to put tender plants — tomatoes, peppers, basil, squash — in the ground. That is the date by which half of years in Woodburn, Oregon are past their last freeze. Harvest before November 14, which leaves roughly 242 frost-free days.
ZIP 97071 sits in USDA hardiness zone 8b, meaning the average coldest night of the year falls between 15 to 20°F. Zone decides what survives the winter; frost dates decide when to plant each spring. They are different questions, and a plant can pass one and fail the other.
These are thirty-year NOAA averages for 1991–2020, not a forecast. Any individual year can frost two to three weeks either side of these dates, so check the actual forecast before planting out.