PlantAlong
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Zone 7b

The coldest winter night here averages 5 to 10°F1. Frost dates vary more than that suggests.

ZIP codes
3,855
Weather stations
639
Last reviewed
Your zone tells you how cold winter gets. It does not tell you when to plant.
Typical last frost
Apr 5most ZIPs Mar 30 – Apr 17
Typical first frost
Nov 1most ZIPs Oct 24 – Nov 14
Spread in spring
18 daysbetween early and late ZIPs
  1. Last spring frostmedian Apr 5
  2. First fall frostmedian Nov 1
  • Frost-free season (median)
Figure 1. When frosts fall across zone 7b: the full range (pale), most ZIP codes (10th to 90th percentile, solid) and the median (marker). From 639 NOAA stations matched to 2,958 ZIP codes.

Zone and frost date are different things. The zone comes from the coldest winter night; frost dates come from spring and fall temperatures at weather stations2. Your own dates can sit anywhere in the range above, so the calendar for your ZIP is the better guide.

Five digits. The calendar is computed on your device.

When to plant in zone 7b

Each crop uses its primary extension source, applied to this zone's frost spread. Rules written for another state are labelled with their source.

  1. Tomatoes
  2. Peppers
  3. Cucumbers
  4. Zucchini
  5. Beans
  6. Peas
  7. Lettuce
  8. Carrots
  9. Onions
  10. Garlic
  11. Potatoes
  12. BasilNo sourced window
  • Start indoors
  • Plant outdoors
  • Range across the zone
  • Frost-free season (median)
  • Spring frost risk (90% to 10%)
  • Fall frost risk (10% to 90%)
Figure 2. Planting windows across zone 7b. Solid and dashed bars: the window at the zone's median frost dates. Pale bars: where the same window falls across most of the zone's ZIP codes.
Table 1. Planting windows in zone 7b.
CropWhatZone medianAcross most of the zoneSource
TomatoesStart indoorsFeb 9Feb 3 – Feb 21Oregon State, central OR3
Transplant outdoorsApr 19Apr 13 – May 1Colorado State4
PeppersStart indoorsFeb 23Feb 17 – Mar 6Oregon State, central OR3
Transplant outdoorsApr 19Apr 13 – May 1Colorado State4
CucumbersStart indoorsMar 22Mar 16 – Apr 3Oregon State, central OR3
Transplant outdoorsApr 12Apr 6 – Apr 24Oregon State, central OR3
Sow outdoorsApr 5Mar 30 – Apr 17Colorado State4
ZucchiniStart indoorsMar 29Mar 23 – Apr 10Oregon State, central OR3
Transplant outdoorsApr 19Apr 13 – May 1Oregon State, central OR3
Sow outdoorsApr 5Mar 30 – Apr 17Colorado State4
BeansStart indoorsMar 15Mar 9 – Mar 27Oregon State, central OR3
Transplant outdoorsApr 12Apr 6 – Apr 24Oregon State, central OR3
Sow outdoorsApr 5Mar 30 – Apr 17Colorado State4
PeasStart indoorsFeb 9Feb 3 – Feb 21Oregon State, central OR3
Transplant outdoorsMar 8Mar 2 – Mar 20Oregon State, central OR3
Sow outdoorsMar 8 – Mar 22Mar 2 – Apr 3Colorado State4
LettuceStart indoorsFeb 16Feb 10 – Feb 28Oregon State, central OR3
Transplant outdoorsMar 22Mar 16 – Apr 3Oregon State, central OR3
Sow outdoorsMar 8 – Mar 22Mar 2 – Apr 3Colorado State4
CarrotsSow outdoorsMar 22 – Apr 5Mar 16 – Apr 17Colorado State4
OnionsStart indoorsDec 15Dec 9 – Dec 27Oregon State, central OR3
Transplant outdoorsFeb 23Feb 17 – Mar 6Oregon State, central OR3
Sow outdoorsMar 8 – Mar 22Mar 2 – Apr 3Colorado State4
GarlicPlant for fallNov 8 – Nov 15Oct 31 – Nov 28Wisconsin5
PotatoesSow outdoorsMar 22 – Apr 5Mar 16 – Apr 17Colorado State4
BasilNo frost-relative rule is published; sources give conditions instead (see the crop page).

Sources

  1. PRISM Group, Oregon State University, 2023 USDA Plant Hardiness Zone Map ZIP code data (PHZM 2023), 2023-11-15. Retrieved 2026-11-02.
  2. NOAA National Centers for Environmental Information, U.S. Climate Normals 2020: U.S. Annual/Seasonal Climate Normals (1991-2020), 2021. Retrieved 2026-11-02.
  3. Oregon State University Extension Service, When to start seeds indoors in central Oregon, reviewed 2024. Retrieved 2026-11-02.
  4. Colorado State University Extension, Vegetable Planting Guide (CMG GardenNotes #720), reviewed September 2024. Retrieved 2026-11-02.
  5. University of Wisconsin–Madison Division of Extension, Wisconsin Horticulture, Garlic, Allium sativum, Rev: 10/2023. Retrieved 2026-11-02.