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USDA hardiness zone lookup

Spokane (North) (99205) — USDA Zone 6b

Spokane (North), Washington · 149-day growing season

Frost dates and growing season for 99205

USDA hardiness zoneZone 6b
Average last spring frostMay 7
Average first fall frostOctober 3
Growing season length~149 days
Temperature range (F)-10 to 0°F
Temperature range (C)-23 to -18°C

These are 50%-probability averages modeled from this ZIP's USDA hardiness zone and regional climate normals — not a single-station reading. In a typical year the last spring frost will have passed by May 7, but in a colder-than-average year it can run 1-2 weeks later. Plant tender crops (tomatoes, peppers, basil) once both soil and night temperatures are consistently warm — a thermometer beats the calendar.

Growing season in Spokane (North)

Spokane (North), Washington sits in USDA Zone 6b, with roughly 149 frost-free days between an average last spring frost around May 7 and a first fall frost around October 3. That is a standard temperate season — most common vegetables finish comfortably, and a single main planting plus one succession round works well.

What grows in Spokane (North)

Spokane (North) falls in USDA Zone 6b, which means the same hardiness constraints apply as the full Zone 6 guide. Vegetables, herbs, and fruit trees rated to Zone 6b (or hardier) will overwinter here in a typical year.

What to plant in Spokane (North) this week

Spokane (North)'s last frost is around May 7. This is the spring transplant window — start tomatoes and peppers indoors if you haven't, and direct-sow cold-tolerant crops now.

Full planting calendar for Spokane (North)

Crop-by-crop sowing, transplant, and harvest dates calibrated to zone 6 averages:

Local microclimate notes

Zone tables give you the average — but Spokane (North)gardens vary. South-facing walls and paved areas can run a full half-zone warmer than the published rating. Low-lying spots, frost pockets, and shaded north sides can run colder. If you've gardened here a few seasons, your own frost record (the last time you actually got frost damage) is more accurate than any national average.

Source and methodology

Hardiness zone from the USDA Plant Hardiness Zone Map (2023 revision). Frost-date and growing-season figures are modeled from this ZIP's USDA hardiness zone and regional NOAA 1991-2020 climate normals — they are zone-level estimates, not a per-station record, so treat them as planning guidance and confirm against your own local frost history. Crop recommendations are drawn from US Cooperative Extension references and curated by the Growli editorial team. Last reviewed May 2026.

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