Boring, OR planting calendar
- USDA zone
- 8b15 to 20 °F
- Last frost
- Mar 27avg, 32°F
- First frost
- Nov 18avg, 32°F
- Growing season
- 239days
Boring, Oregon is in USDA plant hardiness zone 8b. Its average last spring frost is around March 27 and the first fall frost around November 18, giving a growing season of about 239 days (NOAA 1991–2020 normals, 32°F, median). Start tender crops like tomatoes and peppers indoors weeks before the last frost and set them out afterward; sow hardy crops such as peas, spinach, and lettuce before it. The planner below turns those frost dates into a printable per-crop planting calendar.
Boring planting calendar
Each crop's windows are counted from Boring's average frost dates. hatched = start seeds indoors, solid green = plant out, teal = a fall sowing, and the terracotta dot marks the estimated first harvest. Ranges are extension-guide planning guidance, not guarantees.
- Start indoors
- Plant out
- Fall sowing
- First harvest
| Crop | Frost tolerance | Start indoors | Plant out | First harvest | Fall planting |
|---|---|---|---|---|---|
| Tomato | Tender | Jan 30 – Feb 13 | Apr 3 – Apr 10 | Jun 2 – Jun 22 | — |
| Pepper | Very tender | Jan 16 – Jan 30 | Apr 10 – Apr 17 | Jun 9 – Jul 9 | — |
| Cucumber | Tender | Feb 27 – Mar 6 | Apr 3 – Apr 10 | May 23 – Jun 12 | — |
| Summer squash / zucchini | Tender | — | Apr 3 – Apr 10 | May 18 – Jun 2 | — |
| Bush bean | Tender | — | Apr 3 – Apr 10 | May 23 – Jun 2 | Sep 19 – Sep 29 |
| Sweet corn | Tender | — | Mar 27 – Apr 10 | May 26 – Jun 25 | — |
| Basil | Very tender | Feb 13 – Feb 27 | Apr 3 – Apr 10 | May 3 – May 18 | — |
| Lettuce | Half-hardy | Feb 13 – Feb 27 | Feb 27 – Mar 13 | Apr 13 – Apr 28 | Sep 5 – Sep 20 |
| Pea | Hardy | — | Feb 13 – Feb 27 | Apr 9 – Apr 24 | Aug 26 – Sep 10 |
| Spinach | Hardy | — | Feb 13 – Feb 27 | Mar 25 – Apr 4 | Sep 15 – Sep 25 |
| Carrot | Half-hardy | — | Mar 6 – Mar 13 | May 5 – May 25 | Aug 16 – Sep 5 |
| Broccoli | Half-hardy | Jan 30 – Feb 13 | Feb 27 – Mar 13 | Apr 23 – May 13 | Aug 21 – Sep 10 |
Data: NOAA NCEI U.S. Climate Normals 1991–2020 (public domain) and USDA Plant Hardiness Zone Map 2023. Planting windows synthesized from U.S. Cooperative Extension guides.
Frost & freeze dates
From NOAA's 1991–2020 Climate Normals at station USC00353770. The median (p50) is the average date; the 90%-safe column is the date the freeze has passed in about 9 years out of 10 (p10 for spring, p90 for fall) — the conservative date to plant after or harvest before.
| Threshold | Last spring — avg | Last spring — 90%-safe | First fall — avg | First fall — 90%-safe | Season (days) |
|---|---|---|---|---|---|
| 36°F | Apr 26 | May 12 | Oct 29 | Nov 18 | 186 |
| 32°F (freeze) | Mar 27 | Apr 20 | Nov 18 | Dec 10 | 239 |
| 28°F | Feb 14 | Mar 12 | Dec 9 | Jan 19 | 303 |
| 24°F | Jan 16 | Feb 21 | Dec 29 | Feb 9 | 350 |
32°F is the standard "freeze" line that damages tender crops; lighter 36°F frost can nip the most cold-sensitive plants, while hardy crops shrug off light frost down toward 28°F. Use the threshold that matches what you are protecting.
Growing degree days
Growing degree days (GDD) accumulate warmth above a base temperature over the year — a better predictor of crop development than the calendar alone. Warm-season crops need a long, warm GDD total; a short, cool GDD total favors greens and brassicas.
| Model | °F·days | Used for |
|---|---|---|
| Base 50°F (warm-season) | 1,960 | standard warm-season base (tomato, corn, beans) |
| Base 40°F (cool-season) | 4,417 | cool-season crops (brassicas, greens) |
Hardiness zone 8b
Boring sits in USDA plant hardiness zone 8b on the 2023 map — meaning its average annual extreme minimum winter temperature is about 15 to 20 °F. That number tells you which perennials, shrubs, and trees reliably survive an average winter here; it does not set your planting dates, which come from the frost calendar above.
Explore more places in zone 8b, or see all USDA hardiness zones.
Frequently asked questions
- What USDA hardiness zone is Boring?
- Boring, Oregon is in USDA plant hardiness zone 8b on the 2023 map (average annual extreme minimum temperature 15 to 20 °F) — from the USDA Plant Hardiness Zone Map 2023, matched to this location's ZIP. See the methodology page for sources.
- When is the last frost in Boring?
- The average (median) last spring frost at 32°F is around March 27, from NOAA's 1991–2020 climate normals at the nearest reporting station. Roughly one year in ten the last frost is as late as April 20, so wait until then before setting out frost-tender plants if you want to be safe.
- When is the first fall frost in Boring?
- The average first fall frost at 32°F is around November 18. That leaves a growing season of about 239 days between the average last spring and first fall frosts.
- When should I start tomatoes in Boring?
- Start tomato seeds indoors about Jan 30 – Feb 13 and transplant them outside about Apr 3 – Apr 10, once the danger of frost has passed. Estimated first harvest is around Jun 2 – Jun 22.
- How long is the growing season in Boring?
- About 239 days at the 32°F threshold (NOAA 1991–2020, median) — the span between the average last spring frost (~March 27) and the average first fall frost (~November 18). Cold-hardy crops extend usable time at both ends; frost-tender crops fit inside it.
Sources & method
Frost, freeze, growing-season, and growing-degree-day figures are NOAA NCEI U.S. Climate Normals 1991–2020 for station USC00353770 (Headworks Portland Wtr B, 4.7 km away). The hardiness zone is the USDA Plant Hardiness Zone Map 2023, matched to this location's ZIP. Planting windows are computed by counting from the average last and first frost using per-crop offsets synthesized from U.S. Cooperative Extension guides — the full method and citations are on the methodology page.