Cowlitz County, Washington
Local growing conditions for Cowlitz County: the USDA hardiness zones found here, frost dates, and live weather for communities across the county. Based on 10 ZIP codes in our data.
Hardiness zones in Cowlitz County
Cowlitz County spans these USDA plant hardiness zones (by number of ZIP codes):
Local weather & frost dates
Open any community in Cowlitz County for its live forecast, frost dates, and planting calendar:
Ryderwood 98581
Cougar 98603
Kelso 98609
Castle Rock 98611
Amboy 98625
Kelso 98626
Longview 98632
Castle Rock 98645
Mossyrock 98649
Woodland 98674
More for Washington
- Agriculture in Washington
- Frost dates across Washington
- USDA hardiness zones explained
- Planting calendar by ZIP code
County growing conditions are compiled from our ZIP-code database, USDA hardiness-zone data, and NOAA climate normals. Conditions vary within a county by elevation and local microclimate. Page updated Aug 4, 2026.