USDA zone 9b in Oregon

25 to 30 °F avg. annual extreme minimum · 9 locations in this group · NOAA 1991–2020 normals

USDA plant hardiness zone 9b covers 9 locations across Oregon (average annual extreme minimum 25 to 30 °F): Bandon, OR, Harbor, OR, Langlois, OR, Lincoln Beach, OR, Newport, OR, Newport, OR, and 3 more. Average last spring frost across this group ranges January 31 (Harbor) to April 4 (Lincoln Beach), and growing seasons run 227–334 days (Lincoln Beach to Harbor) — even within one state, because hardiness sets winter survival, not planting dates. The table below gives every Oregon location's own frost dates; the printable planting calendar uses Newport, this group's median-season location.

USDA zone
9b25 to 30 °F
Last frost range
Jan 31–Apr 4avg, 32°F
First frost range
Nov 16–Dec 27avg, 32°F
Growing season range
227–334days

Locations in this group

Every location below shares this zone and a nearby weather station, but keeps its own frost dates — find your town for its own numbers, or use the ZIP planner on the home page for an instant personalized answer.

Own frost dates per location.
LocationAlso coversNearest stationLast frostFirst frostSeason (days)
BandonBandon 2 NneMar 9Nov 27260
HarborBrookings 2 SeJan 31Dec 27334
LangloisLanglois #2Mar 16Nov 29258
Lincoln BeachOtis 2 NeApr 4Nov 16227
Newport *Newport 3nMar 12Dec 10271
NewportNewport 1 SeFeb 19Dec 16306
PacificCloverdaleMar 17Nov 22251
Port OrfordPort Orford #2Feb 17Dec 3292
WedderburnGold Beach RsFeb 16Dec 16314

* Newport is this group's median-season location — the calendar below is computed from its data.

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.

Planting calendar (Newport, representative)

Computed from Newport's average frost dates — the median-season location in this Oregonzone 9b group. 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 — your own location's dates may run a week or two earlier or later (see the table above).

  • Start indoors
  • Plant out
  • Fall sowing
  • First harvest
Planting windows for Newport (Oregon, zone 9b), this group's representative location.
CropFrost toleranceStart indoorsPlant outFirst harvestFall plantingSeason fit
TomatoTenderJan 15 – Jan 29Mar 19 – Mar 26May 18 – Jun 7matures comfortably
PepperVery tenderJan 1 – Jan 15Mar 26 – Apr 2May 25 – Jun 24matures comfortably
CucumberTenderFeb 12 – Feb 19Mar 19 – Mar 26May 8 – May 28matures comfortably
Summer squash / zucchiniTenderMar 19 – Mar 26May 3 – May 18matures comfortably
Bush beanTenderMar 19 – Mar 26May 8 – May 18Oct 11 – Oct 21matures comfortably
Sweet cornTenderMar 12 – Mar 26May 11 – Jun 10matures comfortably
BasilVery tenderJan 29 – Feb 12Mar 19 – Mar 26Apr 18 – May 3matures comfortably
LettuceHalf-hardyJan 29 – Feb 12Feb 12 – Feb 26Mar 29 – Apr 13Sep 27 – Oct 12matures comfortably
PeaHardyJan 29 – Feb 12Mar 25 – Apr 9Sep 17 – Oct 2matures comfortably
SpinachHardyJan 29 – Feb 12Mar 10 – Mar 20Oct 7 – Oct 17matures comfortably
CarrotHalf-hardyFeb 19 – Feb 26Apr 20 – May 10Sep 7 – Sep 27matures comfortably
BroccoliHalf-hardyJan 15 – Jan 29Feb 12 – Feb 26Apr 8 – Apr 28Sep 12 – Oct 2matures comfortably

Which crops fit this growing season

Using Newport's own 271-day growing season (32°F, NOAA 1991–2020 median) against each crop's real days-to-maturity range: 12 of 12 crops mature here with comfortable margin. A different location in the table above with a longer or shorter season will get a different mix — the ZIP planner on the home page gives your own.

Frost & freeze dates (Newport)

From NOAA's 1991–2020 Climate Normals at station USC00356035. 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 — the conservative date to plant after or harvest before.

Freeze probabilities by temperature threshold (MM/DD, NOAA 1991–2020), Newport.
ThresholdLast spring — avgLast spring — 90%-safeFirst fall — avgFirst fall — 90%-safeSeason (days)
36°FApr 20May 8Nov 9Dec 9203
32°F (freeze)Mar 12Apr 16Dec 10Feb 8271
28°FJan 28Mar 5Dec 28Feb 20340
24°FJan 4Feb 21Dec 29Feb 18365

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. This group's median GDD (base 50°F) across all 9 locations is 1,611; Newport's own reading is shown below.

Annual growing degree days for Newport (°F·days, NOAA 1991–2020).
Model°F·daysUsed for
Base 50°F (warm-season)1,424standard warm-season base (tomato, corn, beans)
Base 40°F (cool-season)4,509cool-season crops (brassicas, greens)

Hardiness zone 9b in Oregon

Zone 9b means an average annual extreme minimum winter temperature of about 25 to 30 °F on the USDA's 2023 map — the number that 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. Oregon spans 9 hardiness zones in this dataset — see all Oregon locations for the full range, including zones5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a.

Explore zone 9b in other states at zone 9b, or see all USDA hardiness zones.

Frequently asked questions

What does USDA hardiness zone 9b mean in Oregon?
Zone 9b means an average annual extreme minimum winter temperature of 25 to 30 °F — the standard USDA measure of which perennials survive winter. 9 locations in Oregon fall in this zone. It does not set planting dates; see the frost calendar below for that.
Where in Oregon's zone 9b is the growing season longest?
Harbor runs the longest season on this page at about 334 days; Lincoln Beach is shortest at about 227 days — they share the same hardiness zone, but they sit at different weather stations, so their frost calendars differ.
When should I plant tomatoes in Oregon's zone 9b?
Using Newport's frost dates (this page's median-season location): start seeds indoors about Jan 15 – Jan 29, then transplant outside about Mar 19 – Mar 26. Your own location in the table above may differ by a week or two — use the ZIP planner on the home page for your exact station's dates.
Does every location in Oregon's zone 9b have the same frost dates?
No — they do not all share a weather station, so frost dates vary by a week or more across the 9 locations listed (see the table above for each location's own dates).

Sources & method

Frost, freeze, growing-season, and growing-degree-day figures are NOAA NCEI U.S. Climate Normals 1991–2020, one reading per location's own nearest station (see the table above). The hardiness zone is the USDA Plant Hardiness Zone Map 2023, matched to each 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.