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Seasonal Planting Calendar

Updated May 2026 · 0 plants · 0 actions

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Pacific Northwest gets 153 frost-free days — enough room for one full warm-season crop and a quick cool-season second act. September is the editorial lens for what to start, transplant, and direct-seed now. Pick a USDA zone above to compare.

Zone 8b in September

☀️ In-season4 weeks to first frost
September is in-season for Pacific Northwest — your 153-day growing season is the long-form gardening calendar. Direct-seed succession crops, transplant the second wave of brassicas, and stay ahead of weeds and water before the first frost window 4 weeks out.

About Zone 8b

USDA Zone 8b (Pacific Northwest) has an average last frost of May 15 and first frost of Oct 15, giving roughly 153 frost-free days. PNW lowlands (Seattle/Portland metro) — cool summers, mild wet winters. A warm April is a tease, not the season; harden tomatoes off slowly. Sources: Tilth Alliance, WSU Extension & generations of PNW gardeners.

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